adding days to a date

Corrected typo in y4 calculation: [SUB cury y4 y4] is correct; [SUB cury 3 y4] was incorrect.

drbitboy said:

...

Code:

########################################################################
### Exit this routine unless "finished cleaning" one-shot is 1
    
   fin_cln_ons
-------]/[---------<RET>---


########################################################################
### Assume count of days in current month, tag curdim, is 30
    _______________
---[MOV            ]----
   [Source       30]
   [Dest     curdim]
    ---------------


########################################################################
### Calculations to check for leap year
### - Int tag yN is a year evenly divisible by N and near cury
### - Strictly speaking, this calculation is not needed unless curm is 2
### - Assumes modulo instruction is not available
### - No more than y4 is really needed; this will be irrelevant ca. 2100
        _____________
---+---[AND          ]---+---
   |   [SourceA  cury]   |
   |   [SourceB     3]   |
   |   [Dest       y4]   |
   |    -------------    |
   |    _____________    |
   +---[SUB          ]---+
       [SourceA  cury]
       [SourceB    y4]
       [Dest       y4]
        -------------

        _____________
---+---[DIV          ]---+---
   |   [SourceA  cury]   |
   |   [SourceB   100]   |
   |   [Dest     y100]   |
   |    -------------    |
   |    _____________    |
   +---[MUL          ]---+
       [SourceA  y100]
       [SourceB   100]
       [Dest     y100]
        -------------

        _____________
---+---[DIV          ]---+---
   |   [SourceA  cury]   |
   |   [SourceB   400]   |
   |   [Dest     y400]   |
   |    -------------    |
   |    _____________    |
   +---[MUL          ]---+
       [SourceA  y400]
       [SourceB   400]
       [Dest     y400]
        -------------


########################################################################
### Adjust 30d assumption above for Jan, Mar, May, Jul, Aug, Oct, Dec

        _____________   curm/0        __________________
---+---[LES          ]----] [----+---[ADD               ]------
   |   [SourceA  curm]           |   [SourceA     curdim]
   |   [SourceB     8]           |   [SourceB          1]
   |    -------------            |   [Dest        curdim]
   |                             |    ------------------
   |    _____________   curm/0   |
   +---[GRT          ]----]/[----+
       [SourceA  curm]
       [SourceB     7]
        ------------- 


########################################################################
### Adjust 30d assumption above for Feb:
### 30-2 => 28, then +1 => 29 for leap years

    _____________                                                 _______________
---[EQU          ]---+-------------------------------------------[SUB            ]---+--
   [SourceA  curm]   |                                           [SourceA  curdim]   |
   [SourceB     2]   |                                           [SourceB      -2]   |
    -------------    |                                           [Dest     curdim]   |
                     |                                            ---------------    |
                     |    _____________     _____________         _______________    |
                     +---[EQU          ]---[NEQ          ]---+---[ADD            ]---+
                     |   [SourceA  cury]   [SourceA  cury]   |   [SourceA  curdim]
                     |   [SourceB    y4]   [SourceB  y100]   |   [SourceB       1]
                     |    -------------     -------------    |   [Dest     curdim]
                     |    _____________                      |    ---------------
                     +---[EQU          ]---------------------+
                         [SourceA  cury]
                         [SourceB  y400]
                          -------------


########################################################################
### Move cury & curm to nxty & nxtm as initial year and month estimates
### Calculate nxtd, day of month a fortnight hence
### Correct for rollover at end of month


        ____________
---+---[MOV         ]------------------------------+---
   |   [Source  cury]                              |
   |   [Dest    nxtd]                              |
   |    ------------                               |
   |    _____________                              |
   +---[MOV         ]------------------------------+
   |   [Source  curm]                              |
   |   [Dest    nxtm]                              |
   |    ------------                               |
   |    _____________                              |
   +---[ADD          ]-----------------------------+
   |   [SourceA  curd]                             |
   |   [SourceB    14]                             |
   |   [Dest     nxtd]                             |
   |    -------------                              |
   |    _______________         _______________    |
   +---[GRT            ]---+---[SUB            ]---+
       [SourceA    nxtd]   |   [SourceA    nxtd]   |
       [SourceB  curdim]   |   [SourceB  curdim]   |
        ---------------    |   [Dest       nxtd]   |
                           |    ---------------    |
                           |    _____________      |
                           +---[ADD          ]-----+
                               [SourceA  nxtm]
                               [SourceB     1]
                               [Dest     nxtm]
                                -------------


########################################################################
### Correct for rollover at end of year
    _______________         _______________
---[GRT            ]---+---[MOV            ]---+---
   [SourceA    nxtm]   |   [SourceA       1]   |
   [SourceB      12]   |   [SourceB    nxtm]   |
    ---------------    |    ---------------    |
                       |    _____________      |
                       +---[ADD          ]-----+
                           [SourceA  nxty]
                           [SourceB     1]
                           [Dest     nxty]
                            -------------

Kinda makes daba's relative approach more attractive, eh?

Click to expand...

Lare said:

I posted same allready on 2nd post on this thread.

OP answered then that day-mont-year calculation is wanted.
Why everyone aren't answering to 3rd post (dd-mm-yyyy calculation question)?

Click to expand...

Because it's quite ridiculous.

janner_10 said:

Because it's quite ridiculous.

Click to expand...

Maybe, but still what OP wants.
14days add or subtract is posted several times to this thread.

drbitboy said:

Corrected typo in y4 calculation: [SUB cury y4 y4] is correct; [SUB cury 3 y4] was incorrect.

Click to expand...

Where curm/0 bit is setted, as I don't understand how july and august are changed to 31 days?

Lare said:

Where curm/0 bit is setted, as I don't understand how july and august are changed to 31 days?

Click to expand...

months with 31 days before August(8) are Jan(1), Mar(3), May(5), Jul(7) i.e. odd months, so the /0 bit of curm is 1 for 31-day months if curm < 8.


months with 31 days after July(7) are Aug(8), Oct(10), Dec(12) i.e. even months, so the /0 bit of curm is 0 for 31-day months if curm > 7.


See [Knuckle Algorithm] below.


Fortunately Feb(2) is even, although there would be other ways around that.

This approach as written only works for delay periods of less than 29d; at 29d and above, the delay from Jan 31 increments nxtm into March or later i.e. two months at least


That said, it would be cleaner to have 13-element array DPM = [0,31,28,31,30,31,30,31,31,30,31,30,31] in it and get the days-per-month via DPM[curm], leaving only the leap-year check to be coded for Feb.



Knuckle Algorithm


months 1-7 (Jan-Jul) on left hand, four (odd) knuckles, three (even) valleys; months 8-12 (Aug-Dec) on right hand, three (even) knuckles, two (odd) valleys.

Lare said:

Maybe, but still what OP wants.
14days add or subtract is posted several times to this thread.

Click to expand...

Is it? Anyone with a gram of sanity would just put in a 14 day timer. You know that and I know that. This thread may of lead him on the right path.