Is there any way to convert "*" to ".*"?

Is there any way to convert this "*" into this ".*"

My output is this

- 1.8420821237718587592979702094453*x^3 + 3.2914765235937450960079786455026*x^2 - 0.44362298592685589504469589883229*x + 0.023160255314885146854519959447316

Thanks!

Answer 1

[John D'Errico]

Why do you think you need to do so?

In the symbolic expression you refer to, all of the * operators are multiplying a scalar numeric constant times x to some power. This is automatically done by the * operator.

It would have been arguably more important to convert those ^ to .^ operators, since ^ does not trivially do what you may be asking in vectorized form.

So, suppose I have the symbolic expression...

vpa(F)
ans =
- 1.8420821237718587592979702094453*x^3 + 3.2914765235937450960079786455026*x^2 -   0.44362298592685589504469589883229*x + 0.023160255314885146854519959447316

matlabFunction(F)
ans =
  function_handle with value:
    @(x)x.*(-4.436229859268559e-1)+x.^2.*3.291476523593745-x.^3.*1.842082123771859+2.316025531488515e-2

As you can see, matlabFunction did what you wanted, I think. So you CAN do what you wanted.

[madhan ravi]

+1 @John D'Errico wow really cool , wasn't aware of this feature

[Fernando Pérez Lara]

Working, thank you very much.

[John D'Errico]

It is a feature that I seem to forget too often myself. But then there are many capabilities of MATLAB that are easy to miss, especially in any language that continuously (slowly) changes with time, adding new features as we go.

Answer 2

[madhan ravi]

Simple answer is you can't

[Fernando Pérez Lara]

So I supose that I have to do it by hand?

[madhan ravi]

yes but what's wrong with *?

[Fernando Pérez Lara]

>> integral(@(x)(- 1.8420821237718587592979702094453*x^3 + 3.2914765235937450960079786455026*x^2 - 0.44362298592685589504469589883229*x + 0.023160255314885146854519959447316), 0, 1)
Error using  ^ 
Incorrect dimensions for raising a matrix to a power. Check that the matrix is square and the power is a scalar. To perform elementwise matrix powers, use '.^'.

Error in @(x)(-1.8420821237718587592979702094453*x^3+3.2914765235937450960079786455026*x^2-0.44362298592685589504469589883229*x+0.023160255314885146854519959447316)

Error in integralCalc/iterateScalarValued (line 314) fx = FUN(t);

Error in integralCalc/vadapt (line 132) [q,errbnd] = iterateScalarValued(u,tinterval,pathlen);

Error in integralCalc (line 75) [q,errbnd] = vadapt(@AtoBInvTransform,interval);

Error in integral (line 88) Q = integralCalc(fun,a,b,opstruct);

>>

[madhan ravi]

press control+f and replace ^ with .^ in windows

command+f and replace ^ with .^ in Mac

same procedure goes for *

[madhan ravi]

try:

integral(@(x)(- 1.8420821237718587592979702094453.*x.^3 + 3.2914765235937450960079786455026.*x.^2 - 0.44362298592685589504469589883229.*x + 0.023160255314885146854519959447316), 0, 1)

[Fernando Pérez Lara]

Thank you again Mate.

[madhan ravi]

Anytime :)

[John D'Errico]

help matlabFunction

Answer 3

[Walter Roberson]

If you have a character vector holding the expression then you can use vectorize()

(matlabFunction calls vectorize)