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Re: Optimizing the code: way to reduce if, else if-s within the loop?

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Alla _ <modelling.data@gmail.com> writes:
<snip>
> Below are a few issues I face when trying to implement the offsetof():

I'll explain the problem but you really should do this another way.

<snip>
> Here is the struct's typedef (it's before the main function):
> typedef struct data {
>     int       year;
>     double    sales;
>     double    cs_cogs;
>     double    cs_gross_profit;
>     double    cs_sga;
>     double    cs_oper_inc;
>     double    cs_dep_amor;
>     double    cs_oper_prof;
>     double    cs_int_exp;
>     double    cs_gain_loss;
>     double    cs_pretax_inc;
>     double    cs_tax_exp;
>     double    cs_net_inc;
> } data;
<snip>
> /** Function to determine a particular struct member **/
> int find_struct_member(char *name)
> {
>     int offset;
>     if(!strcmp(name, "Sales"))
>     {
>         offset = offsetof(struct data, sales);
>         fprintf(stderr, "offset sales %i\n", offset);
>     }
>     else if (!strcmp(name, "Cost of Goods Sold") ||
>              !strcmp(name, "COGS") )
>     {
>         offset = offsetof(struct data, cs_cogs);
>         fprintf(stderr, "offset cs_cogs %i\n", offset);
>     }
>     else if(!strcmp(name, "Gross Profit"))
>     {
>         offset = offsetof(data, cs_gross_profit);
>         fprintf(stderr, "offset cs_gross_profit %i\n", offset);
>     }
>     else if (!strcmp(name, "\"Selling, General, and Admin Exp\"") ||
>              !strcmp(name, "SG&A") )
>     {
>         offset = offsetof(data, cs_sga);
>         fprintf(stderr, "offset cs_sga %i\n", offset);
>     }
>     else if (!strcmp(name, "Operating Income before Depr") ||
>              !strcmp(name, "Operating Income before Depreciation") )
>     {
>         offset = offsetof(data, cs_oper_inc);
>         fprintf(stderr, "offset cs_oper_inc %i\n", offset);
>     }
>     else if(!strcmp(name, "Depreciation and Amortization"))
>     {
>         offset = offsetof(data, cs_dep_amor);
>         fprintf(stderr, "offset cs_dep_amor %i\n", offset);
>     }
>     else if(!strcmp(name, "Operating Profit"))
>     {
>         offset = offsetof(data, cs_oper_prof);
>         fprintf(stderr, "offset cs_oper_prof %i\n", offset);
>     }
>     else if(!strcmp(name, "Interest Expense"))
>     {
>         offset = offsetof(data, cs_int_exp);
>         fprintf(stderr, "offset cs_int_exp %i\n", offset);
>     }
>     else if(!strcmp(name, "Other Gains and Losses"))
>     {
>         offset = offsetof(data, cs_gain_loss);
>         fprintf(stderr, "offset cs_gain_loss %i\n", offset);
>     }
>     else if(!strcmp(name, "Pretax Income"))
>     {
>         offset = offsetof(data, cs_pretax_inc);
>         fprintf(stderr, "offset cs_pretax_inc %i\n", offset);
>     }
>     else if(!strcmp(name, "Income Tax Expense"))
>     {
>         offset = offsetof(data, cs_tax_exp);
>         fprintf(stderr, "offset cs_tax_exp %i\n", offset);
>     }
>     else if(!strcmp(name, "Net Income"))
>     {
>         offset = offsetof(data, cs_net_inc);
>         fprintf(stderr, "offset cs_net_inc %i\n", offset);
>     }
>     else
>         return -1;
>     return offset;
> }

This is the sort of ode that should be setting of alarm bells.
Computers should do the repetitive things not programmers.  These values
should be an array with named indexes (as per my other post).

<snip>
> /** Function to parse numbers from each line **/
> bool parse_numbers(char *line, int offset, data *dat_years)
> {
>     char *ptr = line;
>     char *not_converted = ptr;
>     int count = 0;
>     
>     //DEBUG
>     fprintf(stderr, "Offset passed to function %i\n", offset);
>
>     while(count < DATA_SIZE)
>     {
>         *((char*)dat_years + offset) = strtod(ptr, &not_converted);

You are trying to to store a double in a char.  You can get most
compiler to warn you that this conversion is likely to loose a lot of
information.

<snip>
-- 
Ben.

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Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-21 08:52 -0800
  Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-21 09:35 -0800
  Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-21 10:28 -0800
    Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-21 23:49 -0800
    Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 00:29 -0800
      Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 10:54 +0000
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 03:28 -0800
          Re: Optimizing the code: way to reduce if, else if-s within the loop? Keith Thompson <kst-u@mib.org> - 2017-01-22 07:44 -0800
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 08:24 -0800
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-22 10:43 -0800
              Re: Optimizing the code: way to reduce if, else if-s within the loop? Keith Thompson <kst-u@mib.org> - 2017-01-22 12:22 -0800
        Re: Optimizing the code: way to reduce if, else if-s within the loop? BartC <bc@freeuk.com> - 2017-01-22 11:33 +0000
          Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 13:23 +0000
            Re: Optimizing the code: way to reduce if, else if-s within the loop? BartC <bc@freeuk.com> - 2017-01-22 13:28 +0000
              Re: Optimizing the code: way to reduce if, else if-s within the loop? Keith Thompson <kst-u@mib.org> - 2017-01-22 07:47 -0800
                Re: Optimizing the code: way to reduce if, else if-s within the loop? BartC <bc@freeuk.com> - 2017-01-22 16:00 +0000
                Re: Optimizing the code: way to reduce if, else if-s within the loop? David Brown <david.brown@hesbynett.no> - 2017-01-22 18:23 +0100
                Re: Optimizing the code: way to reduce if, else if-s within the loop? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-22 13:47 -0500
                Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-22 10:43 -0800
                Re: Optimizing the code: way to reduce if, else if-s within the loop? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-22 13:53 -0500
                Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 18:57 +0000
                Re: Optimizing the code: way to reduce if, else if-s within the loop? BartC <bc@freeuk.com> - 2017-01-22 19:18 +0000
                Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 21:54 +0000
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-23 02:41 -0800
          Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-23 11:20 +0000
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-23 03:53 -0800
              Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-23 12:12 +0000
    Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 03:24 -0800
      Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-22 13:16 +0000
      Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-22 07:47 -0800
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 08:16 -0800
          Re: Optimizing the code: way to reduce if, else if-s within the loop? "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-22 11:54 -0500
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 11:23 -0800
          Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-22 11:08 -0800
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 22:19 -0800
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 22:41 -0800
              Re: Optimizing the code: way to reduce if, else if-s within the loop? Robert Wessel <robertwessel2@yahoo.com> - 2017-01-23 02:17 -0600
              Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-23 02:16 -0800
                Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-23 03:59 -0800
              Re: Optimizing the code: way to reduce if, else if-s within the loop? Keith Thompson <kst-u@mib.org> - 2017-01-23 08:44 -0800
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 08:23 -0800
      Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-22 07:52 -0800
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-22 08:17 -0800
    Re: Optimizing the code: way to reduce if, else if-s within the loop? Richard Heathfield <rjh@cpax.org.uk> - 2017-01-23 17:11 +0000
      Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-23 10:35 -0800
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-23 10:38 -0800
        Re: Optimizing the code: way to reduce if, else if-s within the loop? BartC <bc@freeuk.com> - 2017-01-23 19:06 +0000
        Re: Optimizing the code: way to reduce if, else if-s within the loop? Barry Schwarz <schwarzb@dqel.com> - 2017-01-23 14:31 -0800
          Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-23 21:31 -0800
          Re: Optimizing the code: way to reduce if, else if-s within the loop? Alla _ <modelling.data@gmail.com> - 2017-01-24 01:56 -0800
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Manfred <noname@invalid.add> - 2017-01-24 14:38 +0100
            Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-24 13:57 +0000
  Re: Optimizing the code: way to reduce if, else if-s within the loop? BartC <bc@freeuk.com> - 2017-01-23 12:38 +0000
    Re: Optimizing the code: way to reduce if, else if-s within the loop? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-01-23 15:08 +0000
  Re: Optimizing the code: way to reduce if, else if-s within the loop? m.labanowicz@gmail.com - 2017-01-23 07:08 -0800

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