Dear all, i'm new to the site (and returning to Perl after quite a long break, but i was never a master of any sort)

I'm trying to plan out a program and i'd like to sanity check my objectives just to make sure i'm not a: making more work than i need to, and b: planning something stupid.

Task:
read a CSV file containing columns for |Degree Subject|Entry requirement|

The entry requirement field contains strings such as:

"A minimum of 3 A Levels at ABB for First Year Entry or a minimum of AAB for Second Year Entry. Must include Mathematics and Physics at AB."

"For First Year Entry a minimum of 3 A Levels at BBB or 4 AS at AABB. For Second Year Entry a minimum of an A in the subject selected for Single Honours plus BB, or AB in the subjects selected for Joint Honours plus a further B."

"Three A Levels at ABB. AB required in Mathematics and Physics or a B in Design & Technology or a B in Engineering. If applicant presents with B in Physics, Design & Technology or Engineering, Mathematics must be A grade."

Program plan:
Read in the CSV file to an array/hash (more on this later)

Use regular expressions to determine which subjects are required for each degree subject, and create a column specific to EACH subject and mark whether it is present or not

Write this array/hash to a csv file for output.

Example output:
|Degree Subject|Entry requirement* |Grades|Maths|Physics|Engineering|etc etc

|Chemical Eng |A minimum of 3 A Levels at XXX* for First Year Entry..|ABB |A/B |A/B | |
*(use s/ in regex to indicate which parts have been "detected" for manual checking)

Problems/Puzzles:

1/ Would it be more straighforward to use Text::CSV having created the full matrix of columns manually and then assign values to the relevant fields or check for entries in the dataset and then "create" columns during runtime?

2/ My gut feeling is to use an array (instead of a hash) for this as by my nature (and as C was my first language many moons ago) it seems nice and orderly. Speed performance isn't a critical issue here.

3/ for the REGEX component, it's going to be quite complicated, and there are many variants of field here. I'm contemplating doing one of two strategies a) using a first pass to pull out all unique entries and attempt a regex on them, using this as a reference key to then screen the remainder b) doing the regex in one pass N.B there may be as many as 46,000 row entries, but in terms of unique entries it may be more like 5,000 (which is still loads but easier to check over perhaps)

Delighted for any guidance, even just pointers.

Best wishes, Phil

In reply to CSV regex with hash/array program plan by campus1plb

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.