datanitro：python程序员可以对 excel VBA 说不

Contents

Installation
Excel Interface
Hello World
Calculating Pi
Sample Scripts

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Installation

Download and run DataNitroSetup.exe. You'll be prompted to install several programs.
If you don't have .NET Framework 4, you should install it first. (Our installer will give you an error if it's missing, but most people have it).
To update from an older version, first uninstall it from the control panel, and then run the new installer.

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Excel Interface

When you start Excel, you'll have a new DataNitro tab.

The tab has 8 buttons:

Editor

Launches a custom Idle editor. You can use it, or any other editor, to edit Python code. Once you're done, save it as a .py file and run it.

Python Shell

Launches a python shell you can use to interact with the spreadsheet directly.

import

Adds a script to the imported script list.

remove

Removes the script from the list.

Run

Runs the selected script.

Stop

Stops a running script.

Docs

This links to the documentation.

Live Help

This links to our contact information. You can talk with us on any page by clicking "Chat with us!"

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Hello World

Hello world with DataNitro is short:

Cell("A1").value = "Hello, World!"

That's it!

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Calculating Pi

Let's approximate pi with a Monte Carlo simulation. We'll generate a random 2D point with x and y coordinates between 0 and 1, and see how far it is from the origin; specifically, if it's inside the unit circle. The total area of the points we're choosing from is 1, and the area of the points inside the circle and in our box is pi/4, the fraction of points that fall within our radius should be about pi/4.

We'll use Excel to keep track of our trials, and the variables within each trial. First, let's import random, and label a few cells so we know what's what:

from random import randomCell("A2").value, Cell("A3").value, Cell("A4").value = "Trial:","Hits:","pi is about:"Cell("D1").value, Cell("E1").value, Cell("F1").value = "x","y","x^2 + y^2"

Next, we should decide on the number of trials. Let's allow the user to set a number by entering it in the first cell; otherwise, we'll do 100.

trials = Cell("A1").valueif (type(trials)!= int) or (trials < 1):    trials = 100

Now, we'll run the trials. We'll make a function for this, and keep track of the coordinates of our random points, as well as their distance from the origin, under the headings we made. We'll also keep track of the number of trials.

def pi_calc(n):    while Cell("B2").value < n:        x, y = Cell("D2"), Cell("E2")        r = Cell("F2")        x.value, y.value = random(), random()        r.value = x.value**2 + y.value**2

We need to increment the number of trials each time, and also increment "Hits" if our point falls within the circle.

        Cell("B2").value += 1        if r.value <= 1:            Cell("B3").value += 1

We can now approximate pi as 4 times the fraction of hits to trials:

        Cell("B4").value = 4*float(Cell("B3").value)/Cell("B2").value

Let's add a small delay at the end of each run so we can watch the function update.

from time import sleep...def pi_calc(n):    ...    sleep(0.01)

Finally, let's run our function, making sure to reset the number of trials and number of hits beforehand:

Cell("B2").value, Cell("B3").value = 0,0pi_calc(trials)

We're done! Our finished script:

# Generates approximations of pi.  Put the number of trials you want in A1. More# trials will result in higher accuracy.from random import randomfrom time import sleepdef pi_calc(n):    while Cell("B2").value < n:        x, y = Cell("D2"), Cell("E2")        r = Cell("F2")        x.value, y.value = random(), random()        r.value = x.value**2 + y.value**2        Cell("B2").value += 1        if r.value <= 1:            Cell("B3").value += 1        Cell("B4").value = 4*float(Cell("B3").value)/Cell("B2").value        sleep(0.01)trials = Cell("A1").valueif (type(trials)!= int) or (trials < 1):    trials = 100# sheet setupCell("A2").value, Cell("A3").value, Cell("A4").value = "Trial:","Hits:","pi is about:"Cell("D1").value, Cell("E1").value, Cell("F1").value = "x","y","x^2 + y^2"Cell("B2").value, Cell("B3").value = 0,0pi_calc(trials)

More trials will give greater accuracy - 1000 should be enough to approximate pi to two digits.

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Sample Scripts

DataNitro comes with two sample scripts in the example folder: hello_world.py, a hello world program, and pascal_triangle.py, which prints out Pascal's triangle. You can also download and play withpi.py, a spreadsheet and script for binomial option pricing, and theystockquote script for pulling data from yahoo finance, originally fromhttp://goldb.org/ystockquote.html.

If there are any other examples you'd like to see, or if you come up with one you like, let us know!