# integration equvilants for diff() and dsolve()?

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jg on 20 Jan 2020
Commented: Walter Roberson on 23 Jan 2020
hold all;
clear all;
clc;
close all;
hold on
syms A(z) N beta B0 gamma
cond = A(0) == B0;
eqns = diff(A,z) == beta*(A/N)*(N-A)-gamma*A;
S(z) = dsolve(eqns,cond);
pretty(S);
i used this to diffrentiate and get and equation, is there away to do the same thing with integration?
ie the integral of beta*(A/N)*(N-A)-gamma*A
that could return somthing in teh same way that the pretty() function does?
N (beta - gamma)
----------------------------------------------------------------------
/ / / N beta - N gamma \ \ \
| | log| beta - ---------------- | | |
| | z \ B0 / | |
beta - exp| -N (beta - gamma) | - - ------------------------------ | |
\ \ N N beta - N gamma / /

Dinesh Yadav on 23 Jan 2020
Hi jg,
As diff is used for differentiataion, similarly the command int is used for integration. As for dsolve it solves for a system of ODE's by integrating. So I dont understand what do you mean by dsolve's equivalent in integration.
Hope it helps.

#### 1 Comment

Walter Roberson on 23 Jan 2020
All that I have been able to think of is that instead of the problem structure
eqns = diff(A,z) == beta*(A/N)*(N-A)-gamma*A;
that they perhaps want to set up
eqns = int(A,z) == beta*(A/N)*(N-A)-gamma*A;
and solve that.