Mathematica won't multiply a numeric matrix by a symbolic matrix [duplicate]
Clash Royale CLAN TAG#URR8PPP
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This question already has an answer here:
Why does MatrixForm affect calculations?
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If
I1 = 1,0,1,-1
and
Acl = A , -B*K,C*L, A-B*K-C*L
where A, B, C, and D are not defined in the notebook. When I multiply the two matrices like this:
I1.Acl
Mathematica gives me the following:
Whereas if I don't multiply the I1 and Acl but multiply the contents of the variables directly (with parenthesis around each element of the matrice). Mathematica gives me the answer as I would expect. Like this:
How can I multiply a two symbolic matrices together such that I get an answer that an actual matrice multiplication instead of just displaying what I asked Mathematica to do. I'm sure this is a stupid question, but I searched Stack Exchange for 10 minutes using various search strings. In addition I searched Youtube, and Google.
Wolfram alpha gives me the answer as I would have expected. In the same form as if I had done the multiplication by hand. Mathematica won't.
Mathematica Version 11.3
matrix
edited Oct 1 at 1:05
David G. Stork
21.7k11747
asked Sep 30 at 22:35
frequencydrive
205
marked as duplicate by J. M. is somewhat okay.♦ Oct 1 at 4:02
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
add a comment |Â
up vote
2
down vote
favorite
This question already has an answer here:
Why does MatrixForm affect calculations?
4 answers
If
I1 = 1,0,1,-1
and
Acl = A , -B*K,C*L, A-B*K-C*L
where A, B, C, and D are not defined in the notebook. When I multiply the two matrices like this:
I1.Acl
Mathematica gives me the following:
Whereas if I don't multiply the I1 and Acl but multiply the contents of the variables directly (with parenthesis around each element of the matrice). Mathematica gives me the answer as I would expect. Like this:
How can I multiply a two symbolic matrices together such that I get an answer that an actual matrice multiplication instead of just displaying what I asked Mathematica to do. I'm sure this is a stupid question, but I searched Stack Exchange for 10 minutes using various search strings. In addition I searched Youtube, and Google.
Wolfram alpha gives me the answer as I would have expected. In the same form as if I had done the multiplication by hand. Mathematica won't.
Mathematica Version 11.3
matrix
edited Oct 1 at 1:05
David G. Stork
21.7k11747
asked Sep 30 at 22:35
frequencydrive
205
marked as duplicate by J. M. is somewhat okay.♦ Oct 1 at 4:02
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
Note also that you shouldn't use upper-case symbols in Mathematica. Built-in functions always begin with upper-case letters; and so user-defined functions and all symbolic variables should use lower-case letters. For example, in your case,CandKhave built-in meaning, which could lead to unexpected results (you can tell whether a variable has been assigned a value/definition by the colouring).
– AccidentalFourierTransform
Oct 1 at 1:26
add a comment |Â
up vote
2
down vote
favorite
up vote
2
down vote
favorite
This question already has an answer here:
Why does MatrixForm affect calculations?
4 answers
If
I1 = 1,0,1,-1
and
Acl = A , -B*K,C*L, A-B*K-C*L
where A, B, C, and D are not defined in the notebook. When I multiply the two matrices like this:
I1.Acl
Mathematica gives me the following:
Whereas if I don't multiply the I1 and Acl but multiply the contents of the variables directly (with parenthesis around each element of the matrice). Mathematica gives me the answer as I would expect. Like this:
How can I multiply a two symbolic matrices together such that I get an answer that an actual matrice multiplication instead of just displaying what I asked Mathematica to do. I'm sure this is a stupid question, but I searched Stack Exchange for 10 minutes using various search strings. In addition I searched Youtube, and Google.
Wolfram alpha gives me the answer as I would have expected. In the same form as if I had done the multiplication by hand. Mathematica won't.
Mathematica Version 11.3
matrix
edited Oct 1 at 1:05
David G. Stork
21.7k11747
asked Sep 30 at 22:35
frequencydrive
205
This question already has an answer here:
Why does MatrixForm affect calculations?
4 answers
If
I1 = 1,0,1,-1
and
Acl = A , -B*K,C*L, A-B*K-C*L
where A, B, C, and D are not defined in the notebook. When I multiply the two matrices like this:
I1.Acl
Mathematica gives me the following:
Whereas if I don't multiply the I1 and Acl but multiply the contents of the variables directly (with parenthesis around each element of the matrice). Mathematica gives me the answer as I would expect. Like this:
How can I multiply a two symbolic matrices together such that I get an answer that an actual matrice multiplication instead of just displaying what I asked Mathematica to do. I'm sure this is a stupid question, but I searched Stack Exchange for 10 minutes using various search strings. In addition I searched Youtube, and Google.
Wolfram alpha gives me the answer as I would have expected. In the same form as if I had done the multiplication by hand. Mathematica won't.
Mathematica Version 11.3
This question already has an answer here:
Why does MatrixForm affect calculations?
4 answers
matrix
matrix
edited Oct 1 at 1:05
David G. Stork
21.7k11747
asked Sep 30 at 22:35
frequencydrive
205
edited Oct 1 at 1:05
David G. Stork
21.7k11747
asked Sep 30 at 22:35
frequencydrive
205
edited Oct 1 at 1:05
David G. Stork
21.7k11747
edited Oct 1 at 1:05
David G. Stork
21.7k11747
edited Oct 1 at 1:05
David G. Stork
21.7k11747
21.7k11747
asked Sep 30 at 22:35
frequencydrive
205
asked Sep 30 at 22:35
frequencydrive
205
asked Sep 30 at 22:35
frequencydrive
205
205
marked as duplicate by J. M. is somewhat okay.♦ Oct 1 at 4:02
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
marked as duplicate by J. M. is somewhat okay.♦ Oct 1 at 4:02
This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.
Note also that you shouldn't use upper-case symbols in Mathematica. Built-in functions always begin with upper-case letters; and so user-defined functions and all symbolic variables should use lower-case letters. For example, in your case,CandKhave built-in meaning, which could lead to unexpected results (you can tell whether a variable has been assigned a value/definition by the colouring).
– AccidentalFourierTransform
Oct 1 at 1:26
add a comment |Â
Note also that you shouldn't use upper-case symbols in Mathematica. Built-in functions always begin with upper-case letters; and so user-defined functions and all symbolic variables should use lower-case letters. For example, in your case,CandKhave built-in meaning, which could lead to unexpected results (you can tell whether a variable has been assigned a value/definition by the colouring).
– AccidentalFourierTransform
Oct 1 at 1:26
Note also that you shouldn't use upper-case symbols in Mathematica. Built-in functions always begin with upper-case letters; and so user-defined functions and all symbolic variables should use lower-case letters. For example, in your case,
C and K have built-in meaning, which could lead to unexpected results (you can tell whether a variable has been assigned a value/definition by the colouring).– AccidentalFourierTransform
Oct 1 at 1:26
Note also that you shouldn't use upper-case symbols in Mathematica. Built-in functions always begin with upper-case letters; and so user-defined functions and all symbolic variables should use lower-case letters. For example, in your case,
C and K have built-in meaning, which could lead to unexpected results (you can tell whether a variable has been assigned a value/definition by the colouring).– AccidentalFourierTransform
Oct 1 at 1:26
add a comment |Â
1 Answer
1
active
oldest
votes
up vote
3
down vote
accepted
It looks your I1 matrix is being used while wrapped in a MatrixForm. Otherwise, it works just fine.
1, 0, 1, -1.a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
MatrixForm[1, 0, 1, -1].a, -b k, c l, a - b k - c l
That being said, one could also have
MatrixForm[1, 0, 1, -1][[1]].a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
answered Sep 30 at 23:00
That Gravity Guy
1,436513
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
2
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
add a comment |Â
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
3
down vote
accepted
It looks your I1 matrix is being used while wrapped in a MatrixForm. Otherwise, it works just fine.
1, 0, 1, -1.a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
MatrixForm[1, 0, 1, -1].a, -b k, c l, a - b k - c l
That being said, one could also have
MatrixForm[1, 0, 1, -1][[1]].a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
answered Sep 30 at 23:00
That Gravity Guy
1,436513
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
2
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
add a comment |Â
up vote
3
down vote
accepted
It looks your I1 matrix is being used while wrapped in a MatrixForm. Otherwise, it works just fine.
1, 0, 1, -1.a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
MatrixForm[1, 0, 1, -1].a, -b k, c l, a - b k - c l
That being said, one could also have
MatrixForm[1, 0, 1, -1][[1]].a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
answered Sep 30 at 23:00
That Gravity Guy
1,436513
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
2
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
add a comment |Â
up vote
3
down vote
accepted
up vote
3
down vote
accepted
It looks your I1 matrix is being used while wrapped in a MatrixForm. Otherwise, it works just fine.
1, 0, 1, -1.a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
MatrixForm[1, 0, 1, -1].a, -b k, c l, a - b k - c l
That being said, one could also have
MatrixForm[1, 0, 1, -1][[1]].a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
answered Sep 30 at 23:00
That Gravity Guy
1,436513
It looks your I1 matrix is being used while wrapped in a MatrixForm. Otherwise, it works just fine.
1, 0, 1, -1.a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
MatrixForm[1, 0, 1, -1].a, -b k, c l, a - b k - c l
That being said, one could also have
MatrixForm[1, 0, 1, -1][[1]].a, -b k, c l, a - b k - c l
a, -b k, a - c l, -a + c l
answered Sep 30 at 23:00
That Gravity Guy
1,436513
edited Sep 30 at 23:32
answered Sep 30 at 23:00
That Gravity Guy
1,436513
answered Sep 30 at 23:00
That Gravity Guy
1,436513
answered Sep 30 at 23:00
That Gravity Guy
1,436513
1,436513
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
2
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
add a comment |Â
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
2
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
Oh shoot. I did "wrap" it in MatrixForm. I thought MatrixForm was just a formatting command. I didn't think it did anything to my matrices. Thank you for your reply. That was it.
– frequencydrive
Sep 30 at 23:23
2
2
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
@frequencydrive If you find the answer useful, please consider accepting it as an answer.
– Johu
Sep 30 at 23:29
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
Related: mathematica.stackexchange.com/questions/166709
– John Doty
Sep 30 at 23:47
add a comment |Â
Note also that you shouldn't use upper-case symbols in Mathematica. Built-in functions always begin with upper-case letters; and so user-defined functions and all symbolic variables should use lower-case letters. For example, in your case,
CandKhave built-in meaning, which could lead to unexpected results (you can tell whether a variable has been assigned a value/definition by the colouring).– AccidentalFourierTransform
Oct 1 at 1:26