differentiation

When I try to differentiate a symbol with SymPy I get the following In : x=Symbol('x') In : diff(x,x) Out: 1 When I differentiate the symbol respect to its conjugate the result is In [55]: diff(x,x.conjugate()) Out[55]: 0 However, when I try to differentiate the conjugate of the symbol SymPy doesn't do it In : diff(x.conjugate(),x) Out: Derivative(conjugate(x), x) This is still correct, but the result should be zero. How can I make SimPy perform the derivative of a conjugate? I'm not sure about the mathematics if diff(conjugate(x), x) should be zero. The fact that diff(x,x.conjugate()) gives

Suppose you have a function defined by intervals, such as f(x):=block(if x<0 then x^2 else x^3); When we differentiate it with diff(f(x),x); we get d/dx (if x<0 then x^2 else x^3) whereas I'd like to get (if x<0 then 2*x else 3*x^2) Is there a way to obtain such result? This may help in a simple case: (%i1) f(x):= charfun(x<0)*x^2 + charfun(x>=0)*x^3$ (%i2) gradef(charfun(y), 0)$ (%i3) diff(f(x),x); 2 (%o3) 2 x charfun(x < 0) + 3 x charfun(x >= 0) charfun , gradef You can try also Pw.mac package from Richard Hennessy. Here's a different approach using a simplification rule for "if" expressions

Closed . This question needs to be more focused. It is not currently accepting answers. Learn more . Want to improve this question? Update the question so it focuses on one problem only by editing this post . Closed 4 years ago . 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. Selenium WebDriver is made up of core Java API and it is also known as Selenium 2 Ghost Driver is a pure JavaScript implementation of the WebDriver Wire Protocol for PhantomJS. It's a

I would like to know how to detect and differentiate between touches in a multi-touch view. I have read about a "hash" code, but I don't understand how to use it. I want to know when two of my Sprites are touched at the same time, like as if pressing a chord on two keys of a piano. [EDIT] Here is an example of what I have for my ccTouchesBegan: - (void) ccTouchesBegan:(NSSet*)touches withEvent:(UIEvent*)event { NSSet *allTouches = [event allTouches]; int validTouchCount = 0; for (UITouch* touch in allTouches) { BOOL touchIsValid = FALSE; CGPoint location = [touch locationInView: [touch view]];

I have a problem in using the apache commons math library. I just want to create functions like f(x) = 4x^2 + 2x and I want to compute the derivative of this function --> f'(x) = 8x + 2 I read the article about Differentiation ( http://commons.apache.org/proper/commons-math/userguide/analysis.html , section 4.7). There is an example which I don't understand: int params = 1; int order = 3; double xRealValue = 2.5; DerivativeStructure x = new DerivativeStructure(params, order, 0, xRealValue); DerivativeStructure y = f(x); //COMPILE ERROR System.out.println("y = " + y.getValue(); System.out

We need two matrices of differential operators [B] and [C] such as: B = sympy.Matrix([[ D(x), D(y) ], [ D(y), D(x) ]]) C = sympy.Matrix([[ D(x), D(y) ]]) ans = B * sympy.Matrix([[x*y**2], [x**2*y]]) print ans [x**2 + y**2] [ 4*x*y] ans2 = ans * C print ans2 [2*x, 2*y] [4*y, 4*x] This could also be applied to calculate the curl of a vector field like: culr = sympy.Matrix([[ D(x), D(y), D(z) ]]) field = sympy.Matrix([[ x**2*y, x*y*z, -x**2*y**2 ]]) To solve this using Sympy the following Python class had to be created: import sympy class D( sympy.Derivative ): def __init__( self, var ): super( D