DSolve
Usage Message: DSolve[eqn, y, x] solves a differential equation for the function y, with independent variable x.
DSolve[{eqn1, eqn2, ... }, {y1, y2, ... }, x] solves a list of differential equations. DSolve[eqn, y, {x1, x2, ... }] solves a partial differential
equation. Attributes[DSolve] = {Protected, ReadProtected} Options: DSolveConstants
-> C
Notes:
In version 4.0, DSolve will in some cases return
a list of solutions
instead of a matrix of solutions.
In[1]:= DSolve[{x'[t] == y[t]^2, y'[t] == 1 - y[t],
x[0] == 0, y[0] == 0}, {x, y}, t]
Out[1]= {x -> (-(3/2) - 1/(E^(2*#1)*2) + 2/E^#1 + #1 & ),
y -> (1 - E^(-#1) & )}
To fix this error, you can make an assignmnt to $Pre.
In[2]:= $Pre = (If[(Hold[In[$Line]]/.HoldPattern[$Line]->$Line/.
DownValues[In])[[1, 0]] === DSolve &&
Length[Dimensions[#]] == 1, {#}, #]) &;
In[3]:= DSolve[{x'[t] == y[t]^2, y'[t] == 1 - y[t],
x[0] == 0, y[0] == 0}, {x, y}, t]
Out[3]= {{x -> (-(3/2) - 1/(E^(2*#1)*2) + 2/E^#1 + #1 & ),
y -> (1 - E^(-#1) & )}}
This workaround has not been fully tested.
You can have this run automatically by placing this
http://support.wolfram.com/mathematica/kernel/Symbols/System/DSolve.m
in the location given by
In[4]:= ToFileName[{$TopDirectory, "AddOns", "Autoload",
"DSolve", "Kernel"}, "init.m"]
Additional Online Documentation:
Mathematica 3.0
http://documents.wolfram.com/v3/RefGuide/DSolve.html
Mathematica 4.0
http://documents.wolfram.com/v4/RefGuide/DSolve.html
Questions or comments? Send email to support@wolfram.com.
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