# How to convert the equation to MATLab code

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ayad filemban on 10 Apr 2019
Commented: Walter Roberson on 15 Aug 2022
Help converting
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Walter Roberson on 10 Apr 2019

Thomas Rosin on 10 Apr 2019
Edited: Thomas Rosin on 10 Apr 2019

Walter Roberson on 19 Jul 2020
Edited: Walter Roberson on 19 Jul 2020
1. MATLAB has no implied multiplication. All multiplication must be explicit with either the .* (corresponding elements, which is usually the desired operation) or * (inner product) operators
2. e to a power is coded as exp() the power
3. division is the ./ operator with the / operator being more like multiplying by the pseudo-inverse
4. powers other than e to something, should be the .^ (element at a time) or ^ (matrix power through generalized inner product) operators.
5. square root is usually most clear and efficient using sqrt() but .^0.5 or nthroot() can be used, and sometimes sqrtm() or ^0.5 are appropriate
For the kinds of equations that are shown here, use .* and ./ and .^ instead of * and / and ^

akram mehenni on 2 Feb 2022
𝐸5 = 𝛼. 𝐸3 . √𝐸4
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Walter Roberson on 2 Feb 2022
The equations that were posted have no E3, E4, or E5, so this does not appear to be an answer to the question that was put. How are people to understand this as a solution to the question ?

Marwa Hameed on 12 Aug 2022
Edited: Walter Roberson on 15 Aug 2022
How can I convert this equation to MATLAB ?
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Walter Roberson on 15 Aug 2022
Caution: you have variable names Q_min and Q_max but you are integrating with respect to log(Q) so Q_min and Q_max are limits on log(Q) not limits on Q.
Integrating with respect to a function instead of a variable is always tricky.
Pi = sym(pi);
syms a_0 E G_fi(Q) Q_max Q_min R sigma_Born T log_Q
eqn = sigma_Born == 4*Pi*a_0^2/(T/R) * int(G_fi(exp(log_Q))/(E/R), log_Q, Q_min, Q_max)
eqn = 