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en-us2017 Maplesoft, A Division of Waterloo Maple Inc.Maplesoft Document SystemSat, 21 Jan 2017 23:40:12 GMTSat, 21 Jan 2017 23:40:12 GMTThe questions most recently asked on MaplePrimeshttp://www.mapleprimes.com/images/mapleprimeswhite.jpgMaplePrimes - Newest Questions
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Why are old posts bubbling to the top?
http://www.mapleprimes.com/questions/220926-Why-Are-Old-Posts-Bubbling-To-The-Top?ref=Feed:MaplePrimes:New Questions
<p>I'm seeing older posts bubling to the top without any apparent changes. Perhaps spam is being added to the ends of them and then being deleted is the only thing I can think of.</p>
<p>I'm seeing older posts bubling to the top without any apparent changes. Perhaps spam is being added to the ends of them and then being deleted is the only thing I can think of.</p>
220926Sat, 21 Jan 2017 16:57:23 ZChristopher2222Christopher2222How can I get a point in list of point to write an equation of a plane?
http://www.mapleprimes.com/questions/220915-How-Can-I-Get-A-Point-In-List-Of-Point?ref=Feed:MaplePrimes:New Questions
<p>I want to write a plane passing through a point (in list) and parallel to a plane.</p>
<p><strong>L := [[-14, 2, 3], [-13, -3, 1], [-13, -3, 5], [-13, 0, -2]]:<br>
with(geom3d):<br>
point(A, L[1]):<br>
plane(P, 2*x+3*y+z = 0, [x, y, z]):<br>
n := NormalVector(P):<br>
Equation(plane(Q, [A, n], [x, y, z]));</strong><br>
<br>
I tried<strong> <br>
t[i] := ([seq])(point(M, pt[]), pt in L):<br>
Equation( plane(Q,t[i],n],[x,y,z]),i=1..nops(L));</strong><br>
It is not true. How can I repair it?</p>
<p>I want to write a plane passing through a point (in list) and parallel to a plane.</p>
<p><strong>L := [[-14, 2, 3], [-13, -3, 1], [-13, -3, 5], [-13, 0, -2]]:<br>
with(geom3d):<br>
point(A, L[1]):<br>
plane(P, 2*x+3*y+z = 0, [x, y, z]):<br>
n := NormalVector(P):<br>
Equation(plane(Q, [A, n], [x, y, z]));</strong><br>
<br>
I tried<strong> <br>
t[i] := ([seq])(point(M, pt[]), pt in L):<br>
Equation( plane(Q,t[i],n],[x,y,z]),i=1..nops(L));</strong><br>
It is not true. How can I repair it?</p>
220915Sat, 21 Jan 2017 01:10:17 Zminhthien2016minhthien2016Returning Pointer from C dll using define_external
http://www.mapleprimes.com/questions/220914-Returning-Pointer-From-C-Dll-Using-Defineexternal?ref=Feed:MaplePrimes:New Questions
<p>Dear All, </p>
<p>I am trying to use define_external to use a C dll from inside MAPLE. The C dll exports a function that has a argument of type function pointer which has a return type of pointer. The function itself returns pointers. </p>
<p>Pointers are needed as return types as the C function needs to return arrays. </p>
<p>When I try to pass the C function, as maple procedure as the argument, it errs saying "<strong>Error, (in rk4_vec) number expected for float[8] parameter, got proc () option remember; table( [( 1 ) = HFloat(1.0), ( 2 ) = HFloat(-0.0) ] ) 'procname(args)' end proc</strong>"</p>
<p>rk4_vec is as follows: </p>
<pre class="prettyprint">
rk4_vec := define_external("rk4vec", 't0' :: float[8], 'm' :: integer[4], 'u0' :: ARRAY(1..2,datatype=float[8]), 'dt' :: float[8], 'f' :: PROC('t' :: float[8], 'm' :: integer[4], 'u' :: ARRAY(1..2,datatype=float[8]), 'RETURN' :: REF(float[8])), 'RETURN' ::REF(float[8]), "WRAPPER", LIB="rk4.dll");
</pre>
<p>rk4vec in C looks like this: </p>
<pre class="prettyprint">
double *rk4vec ( double t0, int m, double u0[], double dt,
double *f ( double t, int m, double u[] ) )</pre>
<p>I am passing <strong>f </strong>as :</p>
<pre class="prettyprint">
rk4vec_test_f := proc(t, n, u)
local uprime :: REF(float[8]);
#uprime := Array(n);
uprime(1) := u(2);
uprime(2) := -u(1);
return uprime;
end proc;</pre>
<p>I have tried the RETURN type on the define_external call as : float[8], ARRAY(1..2, datatype=float[8]) , but that didnt work either. I got the idea of using REF from <strong>times2 </strong>example on this <a href="http://de.maplesoft.com/support/help/Maple/view.aspx?path=define_external/types">link</a>.</p>
<p>Any guidance in this matter is highly appreciated. </p>
<p>Attached are the C file, the dll, maple worksheet. Tested on Windows, with 64-bit, Maple 2016 standard. <a href="/view.aspx?sf=220914_question/rk4.zip">rk4.zip</a></p>
<p> </p>
<p>Dear All, </p>
<p>I am trying to use define_external to use a C dll from inside MAPLE. The C dll exports a function that has a argument of type function pointer which has a return type of pointer. The function itself returns pointers. </p>
<p>Pointers are needed as return types as the C function needs to return arrays. </p>
<p>When I try to pass the C function, as maple procedure as the argument, it errs saying "<strong>Error, (in rk4_vec) number expected for float[8] parameter, got proc () option remember; table( [( 1 ) = HFloat(1.0), ( 2 ) = HFloat(-0.0) ] ) 'procname(args)' end proc</strong>"</p>
<p>rk4_vec is as follows: </p>
<pre class="prettyprint">
rk4_vec := define_external("rk4vec", 't0' :: float[8], 'm' :: integer[4], 'u0' :: ARRAY(1..2,datatype=float[8]), 'dt' :: float[8], 'f' :: PROC('t' :: float[8], 'm' :: integer[4], 'u' :: ARRAY(1..2,datatype=float[8]), 'RETURN' :: REF(float[8])), 'RETURN' ::REF(float[8]), "WRAPPER", LIB="rk4.dll");
</pre>
<p>rk4vec in C looks like this: </p>
<pre class="prettyprint">
double *rk4vec ( double t0, int m, double u0[], double dt,
double *f ( double t, int m, double u[] ) )</pre>
<p>I am passing <strong>f </strong>as :</p>
<pre class="prettyprint">
rk4vec_test_f := proc(t, n, u)
local uprime :: REF(float[8]);
#uprime := Array(n);
uprime(1) := u(2);
uprime(2) := -u(1);
return uprime;
end proc;</pre>
<p>I have tried the RETURN type on the define_external call as : float[8], ARRAY(1..2, datatype=float[8]) , but that didnt work either. I got the idea of using REF from <strong>times2 </strong>example on this <a href="http://de.maplesoft.com/support/help/Maple/view.aspx?path=define_external/types">link</a>.</p>
<p>Any guidance in this matter is highly appreciated. </p>
<p>Attached are the C file, the dll, maple worksheet. Tested on Windows, with 64-bit, Maple 2016 standard. <a href="/view.aspx?sf=220914_question/rk4.zip">rk4.zip</a></p>
<p> </p>
220914Sat, 21 Jan 2017 00:30:48 ZchintanpchintanpTable of units
http://www.mapleprimes.com/questions/220913-Table-Of-Units----?ref=Feed:MaplePrimes:New Questions
<p>Funny, I can't seem to find a list of all available units in the help file.</p>
<p>Is there not a listed table of units somewhere?</p>
<p>**edit add** conversion of units I mean. ie. meters, miles, gallons, litres, Pa, etc...</p>
<p>Funny, I can't seem to find a list of all available units in the help file.</p>
<p>Is there not a listed table of units somewhere?</p>
<p>**edit add** conversion of units I mean. ie. meters, miles, gallons, litres, Pa, etc...</p>
220913Fri, 20 Jan 2017 23:30:42 ZChristopher2222Christopher2222How to evaluate expression in _Z
http://www.mapleprimes.com/questions/220912-How-To-Evaluate-Expression-In-Z?ref=Feed:MaplePrimes:New Questions
<p>I wish to solve for k interms of x, e is a constant in the equation<strong> k=x+e*sin(k). </strong>Using the solve function, i got </p>
<p><strong>RootOf(_Z-x-e*sin(_Z)) </strong>and using the function <strong>allvalues(RootOf(_Z-x-e*sin(_Z))) </strong>still gave the same expression in _Z. Please is there a way out because I need the value of <strong>k </strong> as a substitute to another equation. Any help will be highly appreciated.<br>
</p>
<p>I wish to solve for k interms of x, e is a constant in the equation<strong> k=x+e*sin(k). </strong>Using the solve function, i got </p>
<p><strong>RootOf(_Z-x-e*sin(_Z)) </strong>and using the function <strong>allvalues(RootOf(_Z-x-e*sin(_Z))) </strong>still gave the same expression in _Z. Please is there a way out because I need the value of <strong>k </strong> as a substitute to another equation. Any help will be highly appreciated.<br />
</p>
220912Fri, 20 Jan 2017 23:11:20 ZabbeykabirabbeykabirConvert mathematica files to maple
http://www.mapleprimes.com/questions/220911-Convert-Mathematica-Files-To-Maple?ref=Feed:MaplePrimes:New Questions
<p>Ì am trying to convert these two files to maple but i have so far failed. I am new to maple and its still unfamiliar. How do convert these two ( <a href="/view.aspx?sf=220911_question/APO.txt">APO.txt</a>; <a href="/view.aspx?sf=220911_question/APOh.txt">APOh.txt</a>) text documents to maple?</p>
<p>Ì am trying to convert these two files to maple but i have so far failed. I am new to maple and its still unfamiliar. How do convert these two ( <a href="/view.aspx?sf=220911_question/APO.txt">APO.txt</a>; <a href="/view.aspx?sf=220911_question/APOh.txt">APOh.txt</a>) text documents to maple?</p>
220911Fri, 20 Jan 2017 16:22:42 Zgreenloafergreenloafer