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Math Help - probably a simple problem....

  1. #1
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    probably a simple problem....

    Ok, so I'm not a programmer by any means, I'm a geologist - truth be told. I'm working on a melting model of the mantle and don't normally have to get too in depth with my MATLAB scripts.

    I've been trying to use this function fmincon to find a minimum value for this function, but its not outputting believable answers. So I've decided to see if its possible to just brute force find a solution.

    my input is an array, one by ten x=[x1 x2 x3... x10]

    the only possible solutions include the constraint that each progressive element is greater than or equal to the one before it ie x3=>x2=>x1...

    so I want to build a matrix with columns being each possible solution. Values for elements can be between 0 and .4 in increments of .01. I cant input zero, so I need to start at .00001.

    This set up probably sounds pretty idiotic, but I've given up doing this a reasonable way - if someone could just help me construct the right set up of for loops or whatever, that'd be amazing.

    Thanks,

    Canopy
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  2. #2
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    Quote Originally Posted by canopy View Post
    Ok, so I'm not a programmer by any means, I'm a geologist - truth be told. I'm working on a melting model of the mantle and don't normally have to get too in depth with my MATLAB scripts.

    I've been trying to use this function fmincon to find a minimum value for this function, but its not outputting believable answers. So I've decided to see if its possible to just brute force find a solution.

    my input is an array, one by ten x=[x1 x2 x3... x10]

    the only possible solutions include the constraint that each progressive element is greater than or equal to the one before it ie x3=>x2=>x1...

    so I want to build a matrix with columns being each possible solution. Values for elements can be between 0 and .4 in increments of .01. I cant input zero, so I need to start at .00001.

    This set up probably sounds pretty idiotic, but I've given up doing this a reasonable way - if someone could just help me construct the right set up of for loops or whatever, that'd be amazing.

    Thanks,

    Canopy
    That is incomprehensible. Why don't you post the real question.

    CB
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  3. #3
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    real question?

    ok... I'm not sure what you mean by real question... but let me try to be more concise.


    I need to write a matrix with an unknown number of columns, and 10 rows.

    consider each column as a separate entity... here are the constraints on those columns:

    -each element of a column has to be greater than or equal to the element above it.

    -each element of a column has to be between 0 and .4, and possible increments are by .01

    -in place of zero, .00001 must be used

    the matrix should include all possible columns that satisfy these constraints.
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  4. #4
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    one last try

    Let me rephrase that for clarity:

    If my only possible values were 1, 2 and 3, and my columns were only 4 elements tall, I'd want to generate

    0000000000000000000011111111122223
    0000000000111111222311111222322233
    0000111223111223223311223223322333
    0123123233123233233313233233323333


    instead though, I want it to have possible values between 0 and .4 by increments of .01, and be 10 elements tell.

    finally, I cant have actual 0s, I need them to be .00001s instead
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  5. #5
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    Quote Originally Posted by canopy View Post
    Let me rephrase that for clarity:

    If my only possible values were 1, 2 and 3, and my columns were only 4 elements tall, I'd want to generate

    0000000000000000000011111111122223
    0000000000111111222311111222322233
    0000111223111223223311223223322333
    0123123233123233233313233233323333


    instead though, I want it to have possible values between 0 and .4 by increments of .01, and be 10 elements tell.

    finally, I cant have actual 0s, I need them to be .00001s instead
    If you can have zero, what are those thing I highlighted in red?

    did you actually mean this:
    Code:
     
    11111111122223
    111111222311111222322233
    111223111223223311223223322333
    123123233123233233313233233323333
    Is this meant to be an array : ARRAY( ROWS 1 TO 4, COLUMNS 1)

    What would a typical floating point valued array look like?
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  6. #6
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    q

    those 0s are zeros, in this example. But in the actual algo I would need all zeros to be replaced by .00001
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  7. #7
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    From the info supplied, your contraints are not clear.
    I do not know what you are trying to do.
    Do you need sequential data or random data.

    This is a fragment that will generate the entire sequence:


    Code:
     
    StartingValue = 0.00001
    ColumnIncrement = 0.00001
    RowIncrement = 0.01
    
    dim Array( 1 to 10)
    
    for trial = 1 to 41
    for c= 1 to 10
    array(c) = startingvalue + i*columnIncrement + trial*RowIncrement
    next c
    '' run the trial with this data
    next trial
    The above creates the following:
    Code:
          1        2        3        4        5        6        7        8        9        10
     1    0.00001  0.00002  0.00003  0.00004  0.00005  0.00006  0.00007  0.00008  0.00009  0.00010
     2    0.01001  0.01002  0.01003  0.01004  0.01005  0.01006  0.01007  0.01008  0.01009  0.01010
     3    0.02001  0.02002  0.02003  0.02004  0.02005  0.02006  0.02007  0.02008  0.02009  0.02010
     4    0.03001  0.03002  0.03003  0.03004  0.03005  0.03006  0.03007  0.03008  0.03009  0.03010
     5    0.04001  0.04002  0.04003  0.04004  0.04005  0.04006  0.04007  0.04008  0.04009  0.04010
     6    0.05001  0.05002  0.05003  0.05004  0.05005  0.05006  0.05007  0.05008  0.05009  0.05010
     7    0.06001  0.06002  0.06003  0.06004  0.06005  0.06006  0.06007  0.06008  0.06009  0.06010
     8    0.07001  0.07002  0.07003  0.07004  0.07005  0.07006  0.07007  0.07008  0.07009  0.07010
     9    0.08001  0.08002  0.08003  0.08004  0.08005  0.08006  0.08007  0.08008  0.08009  0.08010
    10    0.09001  0.09002  0.09003  0.09004  0.09005  0.09006  0.09007  0.09008  0.09009  0.09010
    11    0.10001  0.10002  0.10003  0.10004  0.10005  0.10006  0.10007  0.10008  0.10009  0.10010
    12    0.11001  0.11002  0.11003  0.11004  0.11005  0.11006  0.11007  0.11008  0.11009  0.11010
    13    0.12001  0.12002  0.12003  0.12004  0.12005  0.12006  0.12007  0.12008  0.12009  0.12010
    14    0.13001  0.13002  0.13003  0.13004  0.13005  0.13006  0.13007  0.13008  0.13009  0.13010
    15    0.14001  0.14002  0.14003  0.14004  0.14005  0.14006  0.14007  0.14008  0.14009  0.14010
    16    0.15001  0.15002  0.15003  0.15004  0.15005  0.15006  0.15007  0.15008  0.15009  0.15010
    17    0.16001  0.16002  0.16003  0.16004  0.16005  0.16006  0.16007  0.16008  0.16009  0.16010
    18    0.17001  0.17002  0.17003  0.17004  0.17005  0.17006  0.17007  0.17008  0.17009  0.17010
    19    0.18001  0.18002  0.18003  0.18004  0.18005  0.18006  0.18007  0.18008  0.18009  0.18010
    20    0.19001  0.19002  0.19003  0.19004  0.19005  0.19006  0.19007  0.19008  0.19009  0.19010
    21    0.20001  0.20002  0.20003  0.20004  0.20005  0.20006  0.20007  0.20008  0.20009  0.20010
    22    0.21001  0.21002  0.21003  0.21004  0.21005  0.21006  0.21007  0.21008  0.21009  0.21010
    23    0.22001  0.22002  0.22003  0.22004  0.22005  0.22006  0.22007  0.22008  0.22009  0.22010
    24    0.23001  0.23002  0.23003  0.23004  0.23005  0.23006  0.23007  0.23008  0.23009  0.23010
    25    0.24001  0.24002  0.24003  0.24004  0.24005  0.24006  0.24007  0.24008  0.24009  0.24010
    26    0.25001  0.25002  0.25003  0.25004  0.25005  0.25006  0.25007  0.25008  0.25009  0.25010
    27    0.26001  0.26002  0.26003  0.26004  0.26005  0.26006  0.26007  0.26008  0.26009  0.26010
    28    0.27001  0.27002  0.27003  0.27004  0.27005  0.27006  0.27007  0.27008  0.27009  0.27010
    29    0.28001  0.28002  0.28003  0.28004  0.28005  0.28006  0.28007  0.28008  0.28009  0.28010
    30    0.29001  0.29002  0.29003  0.29004  0.29005  0.29006  0.29007  0.29008  0.29009  0.29010
    31    0.30001  0.30002  0.30003  0.30004  0.30005  0.30006  0.30007  0.30008  0.30009  0.30010
    32    0.31001  0.31002  0.31003  0.31004  0.31005  0.31006  0.31007  0.31008  0.31009  0.31010
    33    0.32001  0.32002  0.32003  0.32004  0.32005  0.32006  0.32007  0.32008  0.32009  0.32010
    34    0.33001  0.33002  0.33003  0.33004  0.33005  0.33006  0.33007  0.33008  0.33009  0.33010
    35    0.34001  0.34002  0.34003  0.34004  0.34005  0.34006  0.34007  0.34008  0.34009  0.34010
    36    0.35001  0.35002  0.35003  0.35004  0.35005  0.35006  0.35007  0.35008  0.35009  0.35010
    37    0.36001  0.36002  0.36003  0.36004  0.36005  0.36006  0.36007  0.36008  0.36009  0.36010
    38    0.37001  0.37002  0.37003  0.37004  0.37005  0.37006  0.37007  0.37008  0.37009  0.37010
    39    0.38001  0.38002  0.38003  0.38004  0.38005  0.38006  0.38007  0.38008  0.38009  0.38010
    40    0.39001  0.39002  0.39003  0.39004  0.39005  0.39006  0.39007  0.39008  0.39009  0.39010
    41    0.40001  0.40002  0.40003  0.40004  0.40005  0.40006  0.40007  0.40008  0.40009  0.40010
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  8. #8
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    ?

    I'm not totally clear what the example I presented has to do with your matrix there.
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  9. #9
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    The transpose of my matrix above will give you 1 compete iteration as you requested:
    Quote Originally Posted by canopy View Post
    ok...
    I need to write a matrix with an unknown number of columns, and 10 rows.
    It is actually 10 columns in 41 rows, so the transpose will apply.

    consider each column as a separate entity... here are the constraints on those columns:

    -each element of a column has to be greater than or equal to the element above it.

    -each element of a column has to be between 0 and .4, and possible increments are by .01

    -in place of zero, .00001 must be used

    the matrix should include all possible columns that satisfy these constraints.
    The question I have:

    Are you looking for a series with aritimetic increments, geometric increments or random increments?

    Do you want ALL possible values for 0.0001 to 0.4 or do you need all values from 0.01 to 0.40 in random groups of ten (with the constraints mentioned)?

    You could have 40,000 values (ranging from 0.00001 to 0.40) and taking them in groups of 10 to generate your input. That's a lot of brute force.

    Since you are excluding zero, it appears as if the values you seek are logarithmic.

    I am not sure what you are attempting to explain:
    Code:
    0000000000000000000011111111122223
    0000000000111111222311111222322233
    0000111223111223223311223223322333
    0123123233123233233313233233323333
    it looks as if you should have done this:
    Code:
    0.000010.000010.000010.000010.00001....
    0.000010.000010.000010.000010.00001....
    0.000010.000010.000010.000011.00001....
    0.000011.000002.000003.000001.00000...
    The colors are there to indicate the width of the data in each column.

    It is not clear at the moment if you are going to furnish your program 1 column of 10 values, or 40000 columns of data with 10 values per column at the start of the program run.

    Could you provide a few examples of actual data that would be used in your program?
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