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# maximalEntry -- maximal absolute value of the entries of the matrix or matrices

- Usage:
    `m = maximalEntries C`
- Inputs:
  - C, a chain complex, or a Matrix, over ZZ, QQ, or RR
- Outputs:
  - m, a list, of the maximal absolute values of the entries in matrices defining the differential

## Description

For each matrix we compute the of maximal absolute value of the entries

    i1 : setRandomSeed "nice example 2";
     -- setting random seed to 12638458417381289481402307077

    i2 : C=randomChainComplex({1,1,1},{2,2},Height=>10)

           3       5       3
    o2 = ZZ  <-- ZZ  <-- ZZ

         0       1       2

    o2 : ChainComplex

    i3 : C.dd

               3                              5
    o3 = 0 : ZZ  <------------------------- ZZ  : 1
                    | -14 -7  5 5   3   |
                    | 8   13  1 -17 -21 |
                    | -13 -15 1 18  21  |

               5                        3
         1 : ZZ  <------------------- ZZ  : 2
                    | -11 5   -10 |
                    | 26  -29 37  |
                    | 19  -16 23  |
                    | -41 -1  -22 |
                    | 46  -16 38  |

    o3 : ChainComplexMap

    i4 : maximalEntry C

    o4 = {21, 46}

    o4 : List

    i5 : B=randomChainComplex({2,2,4,2,5,2,2},{2,3,3,2,3,3},Height=>5)

           4       7       10       7       10       8       5
    o5 = ZZ  <-- ZZ  <-- ZZ   <-- ZZ  <-- ZZ   <-- ZZ  <-- ZZ

         0       1       2        3       4        5       6

    o5 : ChainComplex

    i6 : maximalEntry B

    o6 = {6, 28, 14, 15, 16, 11}

    o6 : List

    i7 : apply(min B..max B,i->rank HH_i(B**QQ))

    o7 = (2, 2, 4, 2, 5, 2, 2)

    o7 : Sequence

## Ways to use maximalEntry:

- `maximalEntry(ChainComplex)`
- `maximalEntry(Matrix)`

## For the programmer

The object maximalEntry is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/RandomComplexes.m2:385:0.