http://www.mapleprimes.com/questions/35518-Solving-An-ODE-With-ifstatement-2 en-us 2026 Maplesoft, A Division of Waterloo Maple Inc. Maplesoft Document System Fri, 12 Jun 2026 18:24:54 GMT Fri, 12 Jun 2026 18:24:54 GMT The latest answers and comments added to the Question, Solving an ODE with `if`statement 2 http://www.mapleprimes.com/images/mapleprimeswhite.jpg http://www.mapleprimes.com/questions/35518-Solving-An-ODE-With-ifstatement-2 http://www.mapleprimes.com/questions/35518-Solving-An-ODE-With-ifstatement-2?ref=Feed:MaplePrimes:Solving an ODE with `if`statement 2:Comments#answer44152 <p>You might try using piecewise instead of `if` in your differential equation.&nbsp; But it really makes no sense to have a quantity in a differential equation have special values at only a finite number of points, different from what it is everywhere else.&nbsp;&nbsp; And it especially makes no sense for the value everywhere else to be NULL.&nbsp; I really don't understand what you're trying to accomplish with this.</p> <p>You might try using piecewise instead of `if` in your differential equation.&nbsp; But it really makes no sense to have a quantity in a differential equation have special values at only a finite number of points, different from what it is everywhere else.&nbsp;&nbsp; And it especially makes no sense for the value everywhere else to be NULL.&nbsp; I really don't understand what you're trying to accomplish with this.</p> 44152 Sat, 13 Mar 2010 04:45:00 Z Robert Israel Robert Israel http://www.mapleprimes.com/questions/35518-Solving-An-ODE-With-ifstatement-2?ref=Feed:MaplePrimes:Solving an ODE with `if`statement 2:Comments#comment44153 <p>Robert: Thanks for your answwr.</p> <p>I'm trying to calculate only 4 distinct points (at 6, 10, 15 &amp; 20C) using the `if` statements.</p> <p>Unfortunately the `if` statemenrts by themselves work but once in the ODE I cannot get a solution.</p> <p>If piecewise does it, I'll appreciate it if you would show me how.</p> <p>Thanks.</p> <p>Robert: Thanks for your answwr.</p> <p>I'm trying to calculate only 4 distinct points (at 6, 10, 15 &amp; 20C) using the `if` statements.</p> <p>Unfortunately the `if` statemenrts by themselves work but once in the ODE I cannot get a solution.</p> <p>If piecewise does it, I'll appreciate it if you would show me how.</p> <p>Thanks.</p> 44153 Sat, 13 Mar 2010 07:14:36 Z cactus cactus http://www.mapleprimes.com/questions/35518-Solving-An-ODE-With-ifstatement-2?ref=Feed:MaplePrimes:Solving an ODE with `if`statement 2:Comments#comment44154 <p>I'm sorry, but it doesn't make sense.&nbsp; The solution of a differential equation depends on all the values of the functions on an interval, not only on the values at 4 points.</p> <p>I'm sorry, but it doesn't make sense.&nbsp; The solution of a differential equation depends on all the values of the functions on an interval, not only on the values at 4 points.</p> 44154 Sun, 14 Mar 2010 09:39:36 Z Robert Israel Robert Israel