## 40 Reputation

3 years, 169 days

## How to use evalf(Int) options...

Maple 2020

I've been trying to implement numeric integration by using different methods of Int, for example _d01ajc, but when I use it, the following error comes up:

W := -16*(x - 1/2)*x*(t + 2*w)*(ln((m^2 + w*x*(-1 + x))/m^2)*ln(-1/(w*(t + w)*x^2 - w*(t + w)*x + m^2*t)) + ln(-x*w^2*(-1 + x))*ln((x^2 - x)*w + m^2) + ln(1/m^2)*ln((t + w)*(-1 + x)) + ln(-1/(x*w))*ln(m^2) + dilog(x*w^2*(-1 + x)/(w*(t + w)*x^2 - w*(t + w)*x + m^2*t)) - dilog(x*w*(-1 + x)*(t + w)/(w*(t + w)*x^2 - w*(t + w)*x + m^2*t)))/t^3 + 8*(x - 1/2)*((t + w)*x - t/2)*(-t*(w*x^2 + m^2 - w*x)*(t + w)*ln((x^2 - x)*w + m^2) + w*(x*w*(-1 + x)*(t + w)*ln((t + w)/w) + m^2*t*ln(m^2)))*(2*w*x + t)/(w*(t + w)*(w*(t + w)*x^2 - w*(t + w)*x + m^2*t)*t^3*x) + (16*x^2 - 8*x)/(t*w*(-1 + x)) + (2*t*x + 2*w*x - t - 2*w)*(2*w*x + t - 2*w)*(1 - 2*x)*ln((t*x + (-1 + x)*w)/((-1 + x)*w))/(((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)*t^2) + (-1 + 2*x)*(2*m^2 + w*x - w)*(2*w*x^2 + 2*m^2 - 3*w*x + w)*ln(m^2/(m^2 + w*x*(-1 + x)))/(w^2*(-1 + x)^2*((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)) + (-1 + 2*x)*(2*m^2 + w*x - w)*(2*w*x^2 + 2*m^2 - 3*w*x + w)*ln(m^2/(m^2 + w*x*(-1 + x)))/(w^2*(-1 + x)^2*(w*(t + w)*x^2 - w*(t + w)*x + m^2*t)) + (2*w*x + t)*((t + w)*x - t/2)*(x - 1/2)*ln(w^4/(t + w)^4)/(t^2*(w*(t + w)*x^2 - w*(t + w)*x + m^2*t)) - 8*(x - 1/2)*((-2 + 2*x)*w + t)*((-1 + x)*w + (x - 1/2)*t)*((t*x + (-1 + x)*w)*w^2*(-1 + x)^2*ln((t*x + (-1 + x)*w)/((-1 + x)*w)) + (-(t*x + (-1 + x)*w)*((x^2 - x)*w + m^2)*ln((x^2 - x)*w + m^2) + ln(m^2)*m^2*w*(-1 + x))*t)/((t*x + (-1 + x)*w)*w*(-1 + x)*t^3*((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)) + 16*(x - 1/2)*(ln(1/m^2)*ln((t*x + (-1 + x)*w)*(-1 + x)*w/((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)) + ln((x^2 - x)*w + m^2)*ln(1/((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)) + ln((-1 + x)^2*w^2)*ln((x^2 - x)*w + m^2) - dilog((t*x + (-1 + x)*w)*(-1 + x)*w/((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)) + dilog((-1 + x)^2*w^2/((-1 + x)^2*w^2 + w*t*x*(-1 + x) + m^2*t)))*(t*x + 2*(-1 + x)*w)/t^3

f3 := (mm, ss, tt, ww) -> Int(eval(W, [s = ss, t = tt, w = ww, m = mm]), x = 0 .. 1, _d01ajc)

A3 := evalf(f3(1, 3, -2, -1))

Error, (in evalf/int) number expected for float[8] parameter, got 0.+0.*I

What's wrong?

## Is it possible to know if Maple is going...

Maple 18

Is there an option or a tool to know if maple is trying to finish the calculation or if it is in a bucle?

## How to perform this kind of integrals?...

Maple 18

Hello!

I am trying to integrate this function numerically from x=0... 1, by using int and evalf(Int) but maple cannot handle it. Is there another kind of numerical integration?

(2*x-1)^2*(2*n+(5*(2*x-1))*(x-1))*(2*n-5+5*x)*ln(1-(5*(1-x))*x/n)/((1-x)^2*(-2*n-(15*(1-x))*x))

Are there another kind of procedures to do numerical integration?

## How to write an expression with indices?...

Maple 18

I have the following expresion:

G_{ik}=|u_{i} - u_{k}|-(u_{i}-u_{k})^2

Where i, k=1,2,3,4. How can I write this expresion in maple? I want to be able to write G_{1 2} and in the RHS 

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