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Questions tagged [differentiation]

The process of finding a derivative.

In calculus, a branch of mathematics, the derivative is a measure of how a function changes as its input changes. Loosely speaking, a derivative can be thought of as how much one quantity is changing in response to changes in some other quantity.

The derivative of a function at a chosen input value describes the best linear approximation of the function near that input value. For a real-valued function of a single real variable, the derivative at a point equals the slope of the tangent line to the graph of the function at that point. In higher dimensions, the derivative of a function at a point is a linear transformation called the linearization.[1] A closely related notion is the differential of a function.

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What's the best way to calculate a numerical derivative in MATLAB?

(Note: This is intended to be a community Wiki.) Suppose I have a set of points xi = {x0,x1,x2,...xn} and corresponding function values fi = f(xi) = {f0,f1,f2,...,fn}, where f(x) is, in general, an unknown function. (In some situations, we might…
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What is the Difference between Selenium Webdriver and Selenium Ghostdriver?

I want to know difference between Selenium Webdriver and Selenium Ghostdriver. I am also confused as to why selenium Ghostdriver is used? Please give me a brief idea. Thanks in Advance.
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What is differentiable programming?

Native support for differential programming has been added to Swift for the Swift for Tensorflow project. Julia has similar with Zygote. What exactly is differentiable programming? what does it enable? Wikipedia says the programs can be…
joel
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Type-based templating function in C++

I want to write a function that fail-safe accesses std::map. At many places in my code I want to access a std::map by key, but in case the key does not exist, I want to have a kind of default value instead of an exception (which is a lot of code for…
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How do I get the derivative of the function?

How do I get the derivative of the following function? g <- expression(x^2) derivg <- D(g, 'x') derivg # 2 * x g1 <- derivg(2) # Error: could not find function "derivg" I want to find the derivative at x = 2.
mudir_dokandar
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Prevent reordering in derivative output?

A recent post on the Wolfram Blog offered the following function to format derivatives in a more traditional way. pdConv[f_] := TraditionalForm[ f /. Derivative[inds__][g_][vars__] :> Apply[Defer[D[g[vars], ##]] &, Transpose[{{vars},…
telefunkenvf14
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non-uniform spacing with numpy.gradient

I'm not sure how to specify non-uniform spacing when using numpy.gradient. Here's some example code for y = x**2. import numpy as np import matplotlib.pyplot as plt x = [0.0, 2.0, 4.0, 8.0, 16.0] y = [0.0, 4.0, 16.0, 64.0, 256.0] dydx = [0.0, 4.0,…
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OpenCV intrusion detection

For a project of mine, I'm required to process images differences with OpenCV. The goal is to detect an intrusion in a zone. To be a little more clear, here are the inputs and outputs: Inputs: An image of reference A second image from approximately…
user2039318
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Looking for a better method to do Quaternion differentiaton

I have a quaternion (4x1) and an angular velocity vector(3x1) and I call a function to calculates the differential quaternion as explained in this web. The code looks like this: float wx = w.at(0); float wy = w.at(1); float wz =…
Jav_Rock
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How do I use mathematica to implicitly solve differential equations of a single variable?

I'm trying to force Mathematica to implicitly differentiate an ellipse equation of the form: x^2/a^2+y^2/b^2 == 100 with a = 8 and b = 6. The command I'm using looks like this: D[x^2/a^2 + y^2/b^2 == 100/. y -> 3/4*Sqrt[6400-x^2], x] where,…
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Automating Winmerge comparison in Python

I require an assistant with coding a comparison between two tables in python, that is currently done in winmerge. The code is as follows import pandas as pd Last week's table df1=pd.read_csv(r"C:\Users\ri0a\OneDrive - Department of Environment,…
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Obtain the difference between two files

First of all, i searched on the web and stackoverflow for around 3 days and haven't found anything i've been looking for. I am doing a weekly security audit where i get back a .csv file with the IPs and the open ports. They look like…
Daniel S.
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Theano gradient with function on tensors

I have a function that calculates a value of a scalar field on a 3D space, so I feed it 3D tensors for x, y and z coordinates (obtained by numpy.meshgrid) and use elementwise operations everywhere. This works as expected. Now I need to calculate a…
cube
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Derivative Calculator

I'm interested in building a derivative calculator. I've racked my brains over solving the problem, but I haven't found a right solution at all. May you have a hint how to start? Thanks I'm sorry! I clearly want to make symbolic…
burki
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Computing the Jacobian matrix for x^2*y, 5*x+sin(y)

If I have an R^n --> R^m function, how can I create its Jacobian matrix? For instance: expression( x^2*y, 5*x+sin(y) ) # f : R^2 --> R^2 I'd like to have a matrix of expressions like: expression(2*x*y) expression(x^2) expression(5)…
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