samuelbayani / dtale Goto Github PK

• Live Demo
• Animated US COVID-19 Deaths By State
• 3D Scatter Chart
• Surface Chart

D-Tale is the combination of a Flask back-end and a React front-end to bring you an easy way to view & analyze Pandas data structures. It integrates seamlessly with ipython notebooks & python/ipython terminals. Currently this tool supports such Pandas objects as DataFrame, Series, MultiIndex, DatetimeIndex & RangeIndex.

D-Tale was the product of a SAS to Python conversion. What was originally a perl script wrapper on top of SAS's insight function is now a lightweight web client on top of Pandas data structures.

• KDNuggets
• Man Institute (warning: contains deprecated functionality)
• Python Bytes
• FlaskCon 2020
• San Diego Python
• Medium: towards data science
• Medium: Exploratory Data Analysis – Using D-Tale
• EOD Notes: Using python and dtale to analyze correlations

• Pip Install Python YouTube Channel
• machine_learning_2019

• Adventures In Flask While Developing D-Tale

• Where To Get It
• Getting Started
  • Python Terminal
  • Jupyter Notebook
  • Jupyterhub w/ Jupyter Server Proxy
  • Jupyterhub w/ Kubernetes
  • Google Colab
  • Kaggle
  • R with Reticulate
  • Command-line
  • Custom Command-line Loaders
• UI
  • Dimensions/Main Menu
  • Header
  • Editing Cells
  • Main Menu Functions
    • XArray Operations, Describe, Outlier Detection, Custom Filter, Building Columns, Summarize Data, Coverage (Deprecated), Correlations, Heat Map, Highlight Dtypes, Highlight Missing, Highlight Outliers, Highlight Range, Instances, Code Exports, About, Resize, Shutdown
  • Column Menu Functions
    • Filtering, Moving Columns, Hiding Columns, Delete, Rename, Replacements, Lock, Unlock, Sorting, Formats, Column Analysis
  • Charts
  • Hotkeys
  • Menu Functions Depending on Browser Dimensions
• For Developers
  • Cloning
  • Running Tests
  • Linting
  • Formatting JS
  • Docker Development
• Global State/Data Storage
• Startup Behavior
• Documentation
• Dependencies
• Acknowledgements
• License

The source code is currently hosted on GitHub at: https://github.com/man-group/dtale

Binary installers for the latest released version are available at the Python package index and on conda using conda-forge.

# conda
conda install dtale -c conda-forge

# or PyPI
pip install dtale

PyCharm	jupyter

This comes courtesy of PyCharm Feel free to invoke python or ipython directly and use the commands in the screenshot above and it should work

If you run into issues with viewing D-Tale in your browser on Windows please try making Python public under "Allowed Apps" in your Firewall configuration. Here is a nice article: How to Allow Apps to Communicate Through the Windows Firewall

import dtale
import pandas as pd

df = pd.DataFrame([dict(a=1,b=2,c=3)])

# Assigning a reference to a running D-Tale process
d = dtale.show(df)

# Accessing data associated with D-Tale process
tmp = d.data.copy()
tmp['d'] = 4

# Altering data associated with D-Tale process
# FYI: this will clear any front-end settings you have at the time for this process (filter, sorts, formatting)
d.data = tmp

# Shutting down D-Tale process
d.kill()

# using Python's `webbrowser` package it will try and open your server's default browser to this process
d.open_browser()

# There is also some helpful metadata about the process
d._data_id  # the process's data identifier
d._url  # the url to access the process

d2 = dtale.get_instance(d._data_id)  # returns a new reference to the instance running at that data_id

dtale.instances()  # prints a list of all ids & urls of running D-Tale sessions

To help guard against users loading the same data to D-Tale multiple times and thus eating up precious memory, we have a loose check for duplicate input data. The check runs the following:

• Are row & column count the same as a previously loaded piece of data?
• Are the names and order of columns the same as a previously loaded piece of data?

If both these conditions are true then you will be presented with an error and a link to the previously loaded data. Here is an example of how the interaction looks:

Within any jupyter (ipython) notebook executing a cell like this will display a small instance of D-Tale in the output cell. Here are some examples:

dtale.show	assignment	instance

If you are running ipython<=5.0 then you also have the ability to adjust the size of your output cell for the most recent instance displayed:

One thing of note is that a lot of the modal popups you see in the standard browser version will now open separate browser windows for spacial convienence:

Column Menus	Correlations	Describe	Column Analysis	Instances

JupyterHub has an extension that allows to proxy port for user, JupyterHub Server Proxy

To me it seems like this extension might be the best solution to getting D-Tale running within kubernetes. Here's how to use it:

import pandas as pd

import dtale
import dtale.app as dtale_app

dtale_app.JUPYTER_SERVER_PROXY = True

dtale.show(pd.DataFrame([1,2,3]))

Notice the command dtale_app.JUPYTER_SERVER_PROXY = True this will make sure that any D-Tale instance will be served with the jupyter server proxy application root prefix:

/user/{jupyter username}/proxy/{dtale instance port}/

One thing to note is that if you try to look at the _main_url of your D-Tale instance in your notebook it will not include the hostname or port:

import pandas as pd

import dtale
import dtale.app as dtale_app

dtale_app.JUPYTER_SERVER_PROXY = True

d = dtale.show(pd.DataFrame([1,2,3]))
d._main_url # /user/johndoe/proxy/40000/dtale/main/1

This is because it's very hard to promgramatically figure out the host/port that your notebook is running on. So if you want to look at _main_url please be sure to preface it with:

http[s]://[jupyterhub host]:[jupyterhub port]

If for some reason jupyterhub changes their API so that the application root changes you can also override D-Tale's application root by using the app_root parameter to the show() function:

import pandas as pd

import dtale
import dtale.app as dtale_app

dtale.show(pd.DataFrame([1,2,3]), app_root='/user/johndoe/proxy/40000/`)

Using this parameter will only apply the application root to that specific instance so you would have to include it on every call to show().

Please read this post

This is a hosted notebook site and thanks to Colab's internal function google.colab.output.eval_js & the JS function google.colab.kernel.proexyPort users can run D-Tale within their notebooks.

DISCLAIMER: It is import that you set USE_COLAB to true when using D-Tale within this service. Here is an example:

import pandas as pd

import dtale
import dtale.app as dtale_app

dtale_app.USE_COLAB = True

dtale.show(pd.DataFrame([1,2,3]))

If this does not work for you try using USE_NGROK which is described in the next section.

This is yet another hosted notebook site and thanks to the work of flask_ngrok users can run D-Tale within their notebooks.

DISCLAIMER: It is import that you set USE_NGROK to true when using D-Tale within this service. Here is an example:

import pandas as pd

import dtale
import dtale.app as dtale_app

dtale_app.USE_NGROK = True

dtale.show(pd.DataFrame([1,2,3]))

Here are some video tutorials of each:

Service	Tutorial	Addtl Notes
Google Colab
Kaggle		make sure you switch the "Internet" toggle to "On" under settings of your notebook so you can install the egg from pip

It is important to note that using NGROK will limit you to 20 connections per mintue so if you see this error:

Wait a little while and it should allow you to do work again. I am actively working on finding a more sustainable solution similar to what I did for google colab. 🙏

I was able to get D-Tale running in R using reticulate. Here is an example:

library('reticulate')
dtale <- import('dtale')
df <- read.csv('https://vincentarelbundock.github.io/Rdatasets/csv/boot/acme.csv')
dtale$show(df, subprocess=FALSE, open_browser=TRUE)

Now the problem with doing this is that D-Tale is not running as a subprocess so it will block your R console and you'll lose out the following functions:

• manipulating the state of your data from your R console
• adding more data to D-Tale

open_browser=TRUE isn't required and won't work if you don't have a default browser installed on your machine. If you don't use that parameter simply copy & paste the URL that gets printed to your console in the browser of your choice.

I'm going to do some more digging on why R doesn't seem to like using python subprocesses (not sure if it something with how reticulate manages the state of python) and post any findings to this thread.

Here's some helpful links for getting setup:

reticulate

installing python packages

Base CLI options (run dtale --help to see all options available)

Loading data from arctic(high performance datastore for pandas dataframes) (this requires either installing arctic or dtale[arctic])

dtale --arctic-host mongodb://localhost:27027 --arctic-library jdoe.my_lib --arctic-node my_node --arctic-start 20130101 --arctic-end 20161231

Loading data from CSV

dtale --csv-path /home/jdoe/my_csv.csv --csv-parse_dates date

Loading data from JSON

dtale --json-path /home/jdoe/my_json.json --json-parse_dates date

or

dtale --json-path http://json-endpoint --json-parse_dates date

Loading data from a Custom loader

• Using the DTALE_CLI_LOADERS environment variable, specify a path to a location containing some python modules
• Any python module containing the global variables LOADER_KEY & LOADER_PROPS will be picked up as a custom loader
  • LOADER_KEY: the key that will be associated with your loader. By default you are given arctic & csv (if you use one of these are your key it will override these)
  • LOADER_PROPS: the individual props available to be specified.
    • For example, with arctic we have host, library, node, start & end.
    • If you leave this property as an empty list your loader will be treated as a flag. For example, instead of using all the arctic properties we would simply specify --arctic (this wouldn't work well in arctic's case since it depends on all those properties)
• You will also need to specify a function with the following signature def find_loader(kwargs) which returns a function that returns a dataframe or None
• Here is an example of a custom loader:

from dtale.cli.clickutils import get_loader_options

'''
  IMPORTANT!!! This global variable is required for building any customized CLI loader.
  When find loaders on startup it will search for any modules containing the global variable LOADER_KEY.
'''
LOADER_KEY = 'testdata'
LOADER_PROPS = ['rows', 'columns']


def test_data(rows, columns):
    import pandas as pd
    import numpy as np
    import random
    from past.utils import old_div
    from pandas.tseries.offsets import Day
    from dtale.utils import dict_merge
    import string

    now = pd.Timestamp(pd.Timestamp('now').date())
    dates = pd.date_range(now - Day(364), now)
    num_of_securities = max(old_div(rows, len(dates)), 1)  # always have at least one security
    securities = [
        dict(security_id=100000 + sec_id, int_val=random.randint(1, 100000000000),
             str_val=random.choice(string.ascii_letters) * 5)
        for sec_id in range(num_of_securities)
    ]
    data = pd.concat([
        pd.DataFrame([dict_merge(dict(date=date), sd) for sd in securities])
        for date in dates
    ], ignore_index=True)[['date', 'security_id', 'int_val', 'str_val']]

    col_names = ['Col{}'.format(c) for c in range(columns)]
    return pd.concat([data, pd.DataFrame(np.random.randn(len(data), columns), columns=col_names)], axis=1)


# IMPORTANT!!! This function is required for building any customized CLI loader.
def find_loader(kwargs):
    test_data_opts = get_loader_options(LOADER_KEY, kwargs)
    if len([f for f in test_data_opts.values() if f]):
        def _testdata_loader():
            return test_data(int(test_data_opts.get('rows', 1000500)), int(test_data_opts.get('columns', 96)))

        return _testdata_loader
    return None

In this example we simplying building a dataframe with some dummy data based on dimensions specified on the command-line:

• --testdata-rows
• --testdata-columns

Here's how you would use this loader:

DTALE_CLI_LOADERS=./path_to_loaders bash -c 'dtale --testdata-rows 10 --testdata-columns 5'

I am pleased to announce that all CLI loaders will be available within notebooks & consoles. Here are some examples (the last working if you've installed dtale[arctic]):

• dtale.show_csv(path='test.csv', parse_dates=['date'])
• dtale.show_csv(path='http://csv-endpoint', index_col=0)
• dtale.show_json(path='http://json-endpoint', parse_dates=['date'])
• dtale.show_json(path='test.json', parse_dates=['date'])
• dtale.show_arctic(host='host', library='library', node='node', start_date='20200101', end_date='20200101')

Once you have kicked off your D-Tale session please copy & paste the link on the last line of output in your browser

The information in the upper right-hand corner gives grid dimensions

• lower-left => row count
• upper-right => column count
• clicking the triangle displays the menu of standard functions (click outside menu to close it)

The header gives users an idea of what operations have taken place on your data (sorts, filters, hidden columns). These values will be persisted across broswer instances. So if you perform one of these operations and then send a link to one of your colleagues they will see the same thing :)

Notice the "X" icon on the right of each display. Clicking this will remove those operations.

When performing multiple of the same operation the description will become too large to display so the display will truncate the description and if users click it they will be presented with a tooltip where you can crop individual operations. Here are some examples:

Sorts	Filters	Hidden Columns

You may edit any cells in your grid (with the exception of the row indexes or headers, the ladder can be edited using the Rename column menu function).

In order to eddit a cell simply double-click on it. This will convert it into a text-input field and you should see a blinking cursor. It is assumed that the value you type in will match the data type of the column you editing. For example:

• integers -> should be a valid positive or negative integer
• float -> should be a valid positive or negative float
• string -> any valid string will do
• category -> either a pre-existing category or this will create a new category for (so beware!)
• date, timestamp, timedelta -> should be valid string versions of each
• boolean -> any string you input will be converted to lowercase and if it equals "true" then it will make the cell True, otherwise False

Users can make use of two protected values as well:

• "nan" -> numpy.nan
• "inf" -> numpy.inf

To save your change simply press "Enter" or to cancel your changes press "Esc".

If there is a conversion issue with the value you have entered it will display a popup with the specific exception in question.

Here's a quick demo:

• Convert To XArray: If you have are currently viewing a pandas dataframe in D-Tale you will be given this option to convert your data to an xarray.Dataset. It is as simple as selecting one or many columns as an index and then your dataframe will be converted to a dataset (df.set_index([...]).to_xarray()) which makes toggling between indexes slices much easier.

• XArray Dimensions: If you are currently viewing data associated with an xarray.Dataset you will be given the ability to toggle which dimension coordinates you're viewing by clicking this button. You can select values for all, some or none (all data - no filter) of your coordinates and the data displayed in your grid will match your selections. Under the hood the code being executed is as follows: ds.sel(dim1=coord1,...).to_dataframe()

View all the columns & their data types as well as individual details of each column

Data Type	Display	Notes
date
string		If you have less than or equal to 100 unique values they will be displayed at the bottom of your popup
int		Anything with standard numeric classifications (min, max, 25%, 50%, 75%) will have a nice boxplot with the mean (if it exists) displayed as an outlier if you look closely.
float

When viewing integer & float columns in the "Describe" popup you will see in the lower right-hand corner a toggle for Uniques & Outliers.

Outliers	Filter

If you click the "Outliers" toggle this will load the top 100 outliers in your column based on the following code snippet:

s = df[column]
q1 = s.quantile(0.25)
q3 = s.quantile(0.75)
iqr = q3 - q1
iqr_lower = q1 - 1.5 * iqr
iqr_upper = q3 + 1.5 * iqr
outliers = s[(s < iqr_lower) | (s > iqr_upper)]

If you click on the "Apply outlier filter" link this will add an addtional "outlier" filter for this column which can be removed from the header or the custom filter shown in picture above to the right.

Apply a custom pandas query to your data (link to pandas documentation included in popup)

Editing	Result

You can also see any outlier or column filters you've applied (which will be included in addition to your custom query) and remove them if you'd like.

Context Variables are user-defined values passed in via the context_variables argument to dtale.show(); they can be referenced in filters by prefixing the variable name with '@'.

For example, here is how you can use context variables in a pandas query:

import pandas as pd

df = pd.DataFrame([
  dict(name='Joe', age=7),
  dict(name='Bob', age=23),
  dict(name='Ann', age=45),
  dict(name='Cat', age=88),
])
two_oldest_ages = df['age'].nlargest(2)
df.query('age in @two_oldest_ages')

And here is how you would pass that context variable to D-Tale: dtale.show(df, context_variables=dict(two_oldest_ages=two_oldest_ages))

Here's some nice documentation on the performance of pandas queries

This video shows you how to build the following:

• Numeric: adding/subtracting two columns or columns with static values
• Bins: bucketing values using pandas cut & qcut as well as assigning custom labels
• Dates: retrieving date properties (hour, weekday, month...) as well as conversions (month end)
• Random: columns of data type (int, float, string & date) populated with random uniformly distributed values.
• Type Conversion: switch columns from one data type to another, fun. 😄

This is very powerful functionality which allows users to create a new data from currently loaded data. The operations currently available are:

• Aggregation: consolidate data by running different aggregations on columns by a specific index
• Pivot: this is simple wrapper around pandas.Dataframe.pivot and pandas.pivot_table
• Transpose: transpose your data on a index (be careful dataframes can get very wide if your index has many unique values)

Function	Data
No Reshaping

Build custom charts based off your data(powered by plotly/dash).

• The Charts will open in a tab because of the fact there is so much functionality offered there you'll probably want to be able to reference the main grid data in the original tab
• To build a chart you must pick a value for X & Y inputs which effectively drive what data is along the X & Y axes
  • If you are working with a 3-Dimensional chart (heatmap, 3D Scatter, Surface) you'll need to enter a value for the Z axis as well
• Once you have entered all the required axes a chart will be built
• If your data along the x-axis (or combination of x & y in the case of 3D charts) has duplicates you have three options:
  • Specify a group, which will create series for each group
  • Specify an aggregation, you can choose from one of the following: Count, First, Last, Mean, Median, Minimum, Maximum, Standard Deviation, Variance, Mean Absolute Deviation, Product of All Items, Sum, Rolling
    • Specifying a "Rolling" aggregation will also require a Window & a Computation (Correlation, Count, Covariance, Kurtosis, Maximum, Mean, Median, Minimum, Skew, Standard Deviation, Sum or Variance)
    • For heatmaps you will also have access to the "Correlation" aggregation since viewing correlation matrices in heatmaps is very useful. This aggregation is not supported elsewhere
  • Specify both a group & an aggregation
• You now have the ability to toggle between different chart types: line, bar, pie, wordcloud, heatmap, 3D scatter & surface
• If you have specified a group then you have the ability between showing all series in one chart and breaking each series out into its own chart "Chart per Group"

Here are some examples:

Chart Type	Chart	Chart per Group
line
bar
stacked
pie
wordcloud
heatmap
3D scatter
surface
Maps (Scatter GEO)
Maps (Choropleth)

Y-Axis Toggling

Users now have the ability to toggle between 3 different behaviors for their y-axis display:

• Default: selecting this option will use the default behavior that comes with plotly for your chart's y-axis
• Single: this allows users to set the range of all series in your chart to be on the same basis as well as making that basis (min/max) editable
• Multi: this allows users to give each series its own y-axis and making that axis' range editable

Here's a quick tutorial:

And some screenshots:

Default	Single	Multi

With a bar chart that only has a single Y-Axis you have the ability to sort the bars based on the values for the Y-Axis

Pre-sort	Post-sort

Popup Charts

Viewing multiple charts at once and want to separate one out into its own window or simply move one off to the side so you can work on building another for comparison? Well now you can by clicking the "Popup" button 😄

Copy Link

Want to send what you're looking at to someone else? Simply click the "Copy Link" button and it will save a pre-populated chart URL into your clipboard. As long as your D-Tale process is still running when that link is opened you will see your original chart.

Exporting Charts

You can now export your dash charts (with the exception of Wordclouds) to static HTML files which can be emailed to others or saved down to be viewed at a later time. The best part is that all of the javascript for plotly is embedded in these files so the nice zooming, panning, etc is still available! 💥

Exporting CSV

I've been asked about being able to export the data that is contained within your chart to a CSV for further analysis in tools like Excel. This button makes that possible.

Want to run D-Tale in a jupyter notebook and build a chart that will still be displayed even after your D-Tale process has shutdown? Now you can! Here's an example code snippet show how to use it:

import dtale

def test_data():
    import random
    import pandas as pd
    import numpy as np

    df = pd.DataFrame([
        dict(x=i, y=i % 2)
        for i in range(30)
    ])
    rand_data = pd.DataFrame(np.random.randn(len(df), 5), columns=['z{}'.format(j) for j in range(5)])
    return pd.concat([df, rand_data], axis=1)

d = dtale.show(test_data())
d.offline_chart(chart_type='bar', x='x', y='z3', agg='sum')

Pro Tip: If generating offline charts in jupyter notebooks and you run out of memory please add the following to your command-line when starting jupyter

--NotebookApp.iopub_data_rate_limit=1.0e10

Disclaimer: Long Running Chart Requests

If you choose to build a chart that requires a lot of computational resources then it will take some time to run. Based on the way Flask & plotly/dash interact this will block you from performing any other request until it completes. There are two courses of action in this situation:

1. Restart your jupyter notebook kernel or python console
2. Open a new D-Tale session on a different port than the current session. You can do that with the following command: dtale.show(df, port=[any open port], force=True)

If you miss the legacy (non-plotly/dash) charts, not to worry! They are still available from the link in the upper-right corner, but on for a limited time... Here is the documentation for those: Legacy Charts

Your Feedback is Valuable

This is a very powerful feature with many more features that could be offered (linked subplots, different statistical aggregations, etc...) so please submit issues :)

If you have watched the video within the Man Institute blog post you'll notice that there is a "Coverage" popup. This was deprecated with the creation of the "Charts" page. You can create the same coverage chart in that video by choosing the following options in the "Charts" page:

• Type: Line
• X: date
• Y: security_id
• Aggregation: Count or Unique Count

Shows a pearson correlation matrix of all numeric columns against all other numeric columns

• By default, it will show a grid of pearson correlations (filtering available by using drop-down see 2nd table of screenshots)
• If you have a date-type column, you can click an individual cell and see a timeseries of pearson correlations for that column combination
  • Currently if you have multiple date-type columns you will have the ability to toggle between them by way of a drop-down
• Furthermore, you can click on individual points in the timeseries to view the scatter plot of the points going into that correlation

Matrix	Timeseries	Scatter

Col1 Filtered	Col2 Filtered	Col1 & Col2 Filtered

When the data being viewed in D-Tale has date or timestamp columns but for each date/timestamp vlaue there is only one row of data the behavior of the Correlations popup is a little different

• Instead of a timeseries correlation chart the user is given a rolling correlation chart which can have the window (default: 10) altered
• The scatter chart will be created when a user clicks on a point in the rollign correlation chart. The data displayed in the scatter will be for the ranges of dates involved in the rolling correlation for that date.

Data	Correlations

This will hide any non-float or non-int columns (with the exception of the index on the right) and apply a color to the background of each cell.

• Each float is renormalized to be a value between 0 and 1.0
• You have two options for the renormalization
  • By Col: each value is calculated based on the min/max of its column
  • Overall: each value is caluclated by the overall min/max of all the non-hidden float/int columns in the dataset
• Each renormalized value is passed to a color scale of red(0) - yellow(0.5) - green(1.0)

Turn off Heat Map by clicking menu option you previously selected one more time

This is a quick way to check and see if your data has been categorized correctly. By clicking this menu option it will assign a specific background color to each column of a specific data type.

• Any cells which contain nan values will be highlighted in yellow.
• Any string column cells which are empty strings or strings consisting only of spaces will be highlighted in orange.
• ❗will be prepended to any column header which contains missing values.

Highlight any cells for numeric columns which surpass the upper or lower bounds of a custom outlier computation.

• Lower bounds outliers will be on a red scale, where the darker reds will be near the maximum value for the column.
• Upper bounds outliers will be on a blue scale, where the darker blues will be closer to the minimum value for the column.
• ⭐ will be prepended to any column header which contains outliers.

Highlight any range of numeric cells based on three different criteria:

• equals
• greater than
• less than

You can activate as many of these criteria as you'd like nad they will be treated as an "or" expression. For example, (x == 0) or (x < -1) or (x > 1)

Selections	Output

Code Exports are small snippets of code representing the current state of the grid you're viewing including things like:

• columns built
• filtering
• sorting

Other code exports available are:

• Column Analysis
• Correlations (grid, timeseries chart & scatter chart)
• Describe
• Charts built using the Chart Builder

Type	Code Export
Main Grid
Histogram
Describe
Correlation Grid
Correlation Timeseries
Correlation Scatter
Charts

This will give you information about other D-Tale instances are running under your current Python process.

For example, if you ran the following script:

import pandas as pd
import dtale

dtale.show(pd.DataFrame([dict(foo=1, bar=2, biz=3, baz=4, snoopy_D_O_double_gizzle=5)]))
dtale.show(pd.DataFrame([
    dict(a=1, b=2, c=3, d=4),
    dict(a=2, b=3, c=4, d=5),
    dict(a=3, b=4, c=5, d=6),
    dict(a=4, b=5, c=6, d=7)
]))
dtale.show(pd.DataFrame([range(6), range(6), range(6), range(6), range(6), range(6)]), name="foo")

This will make the Instances button available in all 3 of these D-Tale instances. Clicking that button while in the first instance invoked above will give you this popup:

The grid above contains the following information:

• Process: timestamp when the process was started along with the name (if specified in dtale.show())
• Rows: number of rows
• Columns: number of columns
• Column Names: comma-separated string of column names (only first 30 characters, hover for full listing)
• Preview: this button is available any of the non-current instances. Clicking this will bring up left-most 5X5 grid information for that instance
• The row highlighted in green signifys the current D-Tale instance
• Any other row can be clicked to switch to that D-Tale instance

Here is an example of clicking the "Preview" button:

This will give you information about what version of D-Tale you're running as well as if its out of date to whats on PyPi.

Up To Date	Out Of Date

Mostly a fail-safe in the event that your columns are no longer lining up. Click this and should fix that

Pretty self-explanatory, kills your D-Tale session (there is also an auto-kill process that will kill your D-Tale after an hour of inactivity)

These interactive filters come in 3 different types: String, Numeric & Date. Note that you will still have the ability to apply custom filters from the "Filter" popup on the main menu, but it will get applied in addition to any column filters.

Type	Filter	Data Types	Features
String		strings & booleans	The ability to select multiple values based on what exists in the column. Notice the "Show Missing Only" toggle, this will only show up if your column has nan values
Date		dates	Specify a range of dates to filter on based on start & end inputs
Numeric		ints & floats	For integers the "=" will be similar to strings where you can select multiple values based on what exists in the column. You also have access to other operands: <,>,<=,>=,() - "Range exclusve", [] - "Range inclusive".

All column movements are saved on the server so refreshing your browser won't lose them 👌

All column movements are saved on the server so refreshing your browser won't lose them 👌

As simple as it sounds, click this button to delete this column from your dataframe.

Update the name of any column in your dataframe to a name that is not currently in use by your dataframe.

This feature allows users to replace content on their column directly or for safer purposes in a brand new column. Here are the options you have:

Type	Data Types	Description	Menu
Value(s)	all	Replace specific values in a column with raw values, output from another column or an aggregation on your column
Spaces Only	strings	Replace string values consisting only of spaces with raw values
Contains Char/Substring	strings	Replace string values containing a specific character or substring
Scikit-Learn Imputer	numeric	Replace missing values with the output of using different Scikit-Learn imputers like iterative, knn & simple

Here's a quick demo:

Adds your column to "locked" columns

• "locked" means that if you scroll horizontally these columns will stay pinned to the right-hand side
• this is handy when you want to keep track of which date or security_id you're looking at
• by default, any index columns on the data passed to D-Tale will be locked

Removed column from "locked" columns

Applies/removes sorting (Ascending/Descending/Clear) to the column selected

Important: as you add sorts they sort added will be added to the end of the multi-sort. For example:

Apply simple formats to numeric values in your grid

Type	Editing	Result
Numeric
Date
String

Here's a grid of all the formats available with -123456.789 as input:

Based on the data type of a column different charts will be shown.

Chart	Data Types	Sample
Histogram	Float, Int
Value Counts	Int, String, Bool, Date, Category
Category	Float

Histogram can be displayed in any number of bins (default: 20), simply type a new integer value in the bins input

Value Count by default, show the top 100 values ranked by frequency. If you would like to show the least frequent values simply make your number negative (-10 => 10 least frequent value)

Value Count w/ Ordinal you can also apply an ordinal to your Value Count chart by selecting a column (of type int or float) and applying an aggregation (default: sum) to it (sum, mean, etc...) this column will be grouped by the column you're analyzing and the value produced by the aggregation will be used to sort your bars and also displayed in a line. Here's an example:

Category (Category Breakdown) when viewing float columns you can also see them broken down by a categorical column (string, date, int, etc...). This means that when you select a category column this will then display the frequency of each category in a line as well as bars based on the float column you're analyzing grouped by that category and computed by your aggregation (default: mean).

These are key combinations you can use in place of clicking actual buttons to save a little time:

* Does not fire if user is actively editing a cell.

Depending on the dimensions of your browser window the following buttons will not open modals, but rather separate browser windows: Correlations, Describe & Instances (see images from Jupyter Notebook, also Charts will always open in a separate browser window)

Clone the code (git clone ssh://[email protected]:manahl/dtale.git), then start the backend server:

$ git clone ssh://[email protected]:manahl/dtale.git
# install the dependencies
$ python setup.py develop
# start the server
$ python dtale --csv-path /home/jdoe/my_csv.csv --csv-parse_dates date

You can also run dtale from PyDev directly.

You will also want to import javascript dependencies and build the source:

$ npm install
# 1) a persistent server that serves the latest JS:
$ npm run watch
# 2) or one-off build:
$ npm run build

The usual npm test command works:

$ npm test

You can run individual test files:

$ TEST=static/__tests__/dtale/DataViewer-base-test.jsx npm run test-file

You can lint all the JS and CSS to confirm there's nothing obviously wrong with it:

$ npm run lint -s

You can also lint individual JS files:

$ npm run lint-js-file -s -- static/dtale/DataViewer.jsx

You can auto-format code as follows:

$ npm run format

You can build python 27-3 & run D-Tale as follows:

$ yarn run build
$ docker-compose build dtale_2_7
$ docker run -it --network host dtale_2_7:latest
$ python
>>> import pandas as pd
>>> df = pd.DataFrame([dict(a=1,b=2,c=3)])
>>> import dtale
>>> dtale.show(df)

Then view your D-Tale instance in your browser using the link that gets printed

You can build python 36-1 & run D-Tale as follows:

$ yarn run build
$ docker-compose build dtale_3_6
$ docker run -it --network host dtale_3_6:latest
$ python
>>> import pandas as pd
>>> df = pd.DataFrame([dict(a=1,b=2,c=3)])
>>> import dtale
>>> dtale.show(df)

Then view your D-Tale instance in your browser using the link that gets printed

If D-Tale is running in an environment with multiple python processes (ex: on a web server running gunicorn) it will most likely encounter issues with inconsistent state. Developers can fix this by configuring the system D-Tale uses for storing data. Detailed documentation is available here: Data Storage and managing Global State

Here's a little background on how the dtale.show() function works:

• by default it will look for ports between 40000 & 49000, but you can change that range by specifying the environment variables DTALE_MIN_PORT & DTALE_MAX_PORT
• think of sessions as python consoles or jupyter notebooks

1. Session 1 executes dtale.show(df) our state is:

2. Session 1 executes dtale.show(df) our state is:

2. Session 2 executes dtale.show(df) our state is:

3. Session 1 executes dtale.show(df, port=40001, force=True) our state is:

4. Session 3 executes dtale.show(df) our state is:

5. Session 2 executes dtale.show(df) our state is:

6. Session 4 executes dtale.show(df, port=8080) our state is:

7. Session 1 executes dtale.get_instance(1).kill() our state is:

7. Session 5 sets DTALE_MIN_RANGE to 30000 and DTALE_MAX_RANGE 39000 and executes dtale.show(df) our state is:

Have a look at the detailed documentation.

• Back-end
  • dash
  • dash_daq
  • Flask
  • Flask-Compress
  • flask-ngrok
  • Pandas
  • plotly
  • scikit-learn
  • scipy
  • xarray
  • arctic [extra]
  • redis [extra]
  • rpy2 [extra]
• Front-end
  • react-virtualized
  • chart.js

D-Tale has been under active development at Man Numeric since 2019.

Original concept and implementation: Andrew Schonfeld

Contributors:

• Phillip Dupuis
• Fernando Saravia Rajal
• Dominik Christ
• Reza Moshksar
• Bertrand Nouvel
• Chris Boddy
• Jason Holden
• Tom Taylor
• Wilfred Hughes
• Mike Kelly
• Vincent Riemer
• Youssef Habchi - title font
• ... and many others ...

Contributions welcome!

D-Tale is licensed under the GNU LGPL v2.1. A copy of which is included in LICENSE