Bruce McCarl's GAMS Newsletter Number 37

Transcription

1 Bruce McCrl's GAMS Newsletter Number 37 This newsletter covers 1 Uptes to Expne GAMS User Guie by McCrl et l YouTube vieos Explntory text for tuple set elements Reing sets using GDXXRW Exmples of t input: Exmples of t output: Bckwr comptibility Skipping over rows n columns in spresheet Courses offere Unsubscribe or subscribe to future issues of this newsletter Uptes to Expne GAMS User Guie by McCrl et l. I upte the Expne User s Guie to reflect the items iscusse here with few other chnges. The ltest cn be foun t n will be in upcoming GAMS releses. 2 YouTube vieos GAMS hs been mking series of tutoril vieos covering vrious topics rnging from bsic instlltion to more vnce t trnsfers. There vieos re t the web pge Ones there s of this writing re A Brief Introuction to Moeling in GAMS Instll the Winows Version of GAMS on Mc by Using Wine How to Instll the Ntive GAMS Version on Mc How to Instll the Ntive GAMS Version on Linux GAMS License File Instlltion n Component Review GAMS n Excel - Using GDX to Trnsfer Dt Using Solver Option File An Introuction to Sets in GAMS Where to Fin Help in Using GAMS GAMS n Mtlb GDXMRW tools RGDX n WGDX GAMS n Mtlb GDXMRW tools IRGDX n IWGDX GAMS n Mtlb Setup n Introuction to GDXMRW 3 Explntory text for tuple set elements I i not know until recently tht one cn explntory text to multiimensionl set (tuple) elements. An exmple is 1

2 set 1 /1,2/ e1 /e1,e2/ f1 /f1,f2/ tuplewithexp(1,e1,f1)/ 1.e1.f1 hs text 2.e2.f2/ where the re entry is the explntory text. This text cn lso come from spresheet s iscusse next. 4 Reing sets using GDXXRW When employing GDXXRW one cn re Sets n ssocite explntory text from spresheet. This is prtilly controlle by the Vlues= option n recently tht option hs been ltere with some chnges in the behvior of the commns. Sets my be input in two wys epening on whether to permit ccommotion of uplicte entries. In output DSET n SET re the sme. The syntx is Set =nmeofset Rng=DtRnge Dimensions Vlues=vlueoptions SymbolOptions Dset=nmeofset Rng=DtRnge Dimensions SymbolOptions where Set= ientifies one is to input or output set elements n optionlly n ssocite set of element explntory text or inictors. on input uplictes will cuse re errors. When writing the element nme is lwys written n the explntory text will be written if the rnge specifiction permits. The keywor Set lso is ssocite with option vlues which inictes how non zero entries in the rnge re to be interprete. Nmely when t re input n vlueoptions equls Auto Bse on the rnge, row n column imensions for the set, the progrm ecies on the vlue type to be use selecting from ense or YN. This is the efult for Vlues. when Auto or vlues entry is not entere n thus the efult is ctive then the import of t behves ifferently epening on the vlues of rim n cim. Nmely If Only one of Rim n Cim re non zero (ie if Rim = 0 or Cim = 0 n the t re in vector form) then the import behves s if NoDt YN Vlues=Dense Both Rim n Cim re non zero n the t re in tbulr form then the import behves s if Vlues=YN The t entries in the rnge for the set will be ignore n ll entries will be inclue without reing explntory text. Only those items will be inclue tht hve non empty t cell in the rnge where the cell contents tht o not equl '0', 'N' or 'No'. 2

3 Sprse Dense Only those items will be inclue tht hve non empty t cell in the rnge. The string in the t cell will be use s the explntory text for the set entry. All items will be inclue tht re in the rnge regrless of whether they hve entries. Any strings in the t cells in the rnge will be use s the explntory text for the set elements. For bckwr comptibility, the vlues String n All re lso recognize n re synonyms to Dense. However when t re output n the vlueoptions equls Auto NoDt YN String Bse on the rnge, row n column imensions for the set, the progrm ecies on the vlue type to be use selecting from String or YN. This is the efult for Vlues. When Auto or vlues entry is not entere n thus the efult is ctive then the import of t behves ifferently epening on the vules of rim n cim. Nmely If Only one of Rim n Cim re non zero (ie if Rim = 0 or Cim = 0 n the t re in vector form) then the import behves s if Vlues=String Both Rim n Cim re non zero n the t re in tbulr form then the import behves s if Vlues=YN The cells in the rnge for the set will be blnk. Only those items will be inclue tht hve non empty t n the cell vlue in the rnge is Y if the element exists. Only those items will be inclue tht hve non empty t n the cell vlue in the rnge is the explntory text if the element exists.. For bckwr comptibility, the vlues Sprse, Dense, n All re lso recognize n re synonyms to String. Dset= Res set of strings from fiel in the spresheet n enters the unique ones into the set. Duplicte lbels in the rnge specifie o not generte n error messge. Dset cnnot be use to write to the spresheet. The vlues prmeter is not use for Dset. 4.1 Exmples of t input: In the input sheet of the spresheet we hve the t for the sets to be importe 3

4 n we hve n inex portion of the sheet (s iscusse in the McCrl guie) telling us how to import with some comments e t the fr right then we import the sets in GAMS using the commns $cll gxxrw trytuple.xlsx o=gxtuple.gx inex=input!i2 $gxin gxtuple.gx 1,1v2,1v3,1v4,1v5,1v6,b1,tuple1 4

5 $gxin tuple1v2 tuple1v3 tuple1v4 tuple1v5 tuple1v6 b1 b2 b3 tuple2 tuple2v2 tuple2v3 c1 c2 c3 tuple3 tuple3v2 tuple3v3 Now let us exmine some of the consequences of the vlue commns. First let us look t the lterntive results for importing the set in the re box below n lso look t the effect of the entries in the blue box When re with the vlues entry being blnk (or the efult - uto conition) the put file t the bottom of the gms file for the set 1 shows it to contin hello b b c n y which shows the reing process went beyon the specifie rnge to the jcent column n took entries there s explntory text leving it bnk when none ws entere but in put sense when it is empty the.tl item is entere in plce of.tl. Also using uto n ense yiels the sme results. When re with the vlues entry being yn we get 5

6 Note here only n entries re efine s they hve text entries in the blue column tht n not N. Also this shows tht the yn entry is misnomer but rther the progrm ccepts ny entry which is not blnk or N or NO or 0. When re with the vlues entry being sprse we get Note here only n entries re efine s they hve text entries in the blue column tht n not N. Also this shows tht the yn entry is misnomer but rther the progrm ccepts ny entry which is not blnk or N or NO or 0. When re with the vlues entry being not we get b b c c Here ll elements re efine s uner ense but the explntory text is not re n only element nmes re use when.te is reference. Now suppose we turn to two imensionl sets or more generlly tuples. When reing tuple1 from the spresheet re in the green box below If we re it with the vlues entry being blnk (or the efult - uto conition) the put file t the bottom of the gms file for the set tuple1 shows it to contin b.2 b.2 b.3 b.3 c.3 c which shows the reing process operte s yn only efining entries with non blnk text n not using tht text for explntory text. Also using uto n yn yiels the sme results. 6

7 When re with the vlues entry being ense we get.1 hello no.4 yes b.1 b.1 b.2 w2 b.3 y b.4 b.4 c.1 n c.2 c.2 c.3 z2 c.4 c.4.1 y z Note here only ll possible entries re efine with the non empty elements being use s explntory text n when blnk the.tl element is printe when.te is reference. When re with the vlues entry being sprse we get.1 hello.3 no.4 yes b.2 w2 b.3 y c.1 n c.3 z2.1 y.4 z which efines tuple entries when there is ssocite text entries incluing those with N or no. When re with the vlues entry being not we get b.1 b.1 b.2 b.2 b.3 b.3 b.4 b.4 7

8 c.1 c.1 c.2 c.2 c.3 c.3 c.4 c Here ll elements re efine s uner ense but the explntory text is not re n only element nmes re use when.te is reference. 4.2 Exmples of t output: This ws lso run to output items into n output sheet from the gx file generte when running the input exmples file telling where to plce the t n wht to o with explntory text. When putting out the set tuple1v4 with the vlue being blnk or set to yn or set to uto we get When putting out the set tuple1v4 with the vlue set to string we get When putting out the set tuple1v4 with the vlue set to not we get where the rnge entries re blnk. 4.3 Bckwr comptibility When inputting sets the menings of the commns hve chnge over time with the current entries not being. In prticulr Before version 24.3 the commn string ws the sme s ense bove Strting with 24.3 the commn string becme the sme s sprse bove 8

9 Strting with the commn ll ws introuce n it functione like ense bove Strting with the commn structure for vlues becme wht is ocumente bove with the option string reefine With these chnges GAMS broke bckwr comptibility. Becuse of this, users who employe the vlues option for the versions before nees to review the wys their input is working n if neee either chnge the prmeters for the GDXXRW cll to the pproprite one of those escribe bove or chnge the workbook t. 5 Skipping over rows n columns in spresheet Spresheet files my contin columns n rows you o not wnt to re. For blnk rows or columns the skipempty commn cn be use s iscusse in the McCrl Guie. For rows or columns tht you o not wnt to re which hve content the IgnoreColumns n IgnoreRows commns ientify rows n columns to skip over. This is one using the syntx IgnoreColumns=comm elimite list of spresheet column nmes IgnoreRows=comm elimite list of spresheet row numbers where The comm elimite list of spresheet column nmes gives the nmes of columns in the rnge to skip over n is of the form A,C,Z,ZZ which woul cuse the reing to skip the columns lbele A,C,Z, n ZZ in the Excel worksheet The comm elimite list of spresheet row nmes gives the nmes of rows in the rnge to skip over n is of the form 2,12,210 which woul cuse the reing to skip the rows lbele 2, 12 n 210 in the Excel worksheet An exmple of using IgnoreRows n IgnoreColumns is s follows. Suppose we hve spresheet tble tht hs rows n columns we o not wnt to re. For this we employ the skipempty sheet of the workbook gxxrwss.xls tht is prt of the McCrl Expne users Guie s in the screen shot below n skip the rows in the re boxes n the column in the blue box n we re it using $cll "gxxrw gxxrwss.xls o=gxignore.gx se=0 pr=moe5 rng=skipempty!2:g69 rim=2 cim=1 IgnoreRows=3,5 IgnoreColumns=D" then fter loing into GAMS the t become 9

10 ship ril brussels.chicgo sn frncisco.chicgo which omits entries from those rows n columns. Note The IgnoreRows n IgnoreColumns prmeters pper fter ny prmeter, set, set etc GDXXRW commn instruction n only ffect reing of tht item. This option will be inclue in the upcoming mjor relese Courses offere I will be teching Bsic to Avnce GAMS clss Aug 10, Aug 14, 2015 (5 ys) in the Coloro mountins t Frisco (ner Breckenrige). The course spns from Bsic topics to n Avnce GAMS clss. Detils re foun t Bsic GAMS clss Aug 10, Aug 12, 2015 (3 ys) in the Coloro mountins t Frisco (ner Breckenrige). The course strts ssuming no GAMS bckgroun. Detils re given t Avnce GAMS clss Aug 12, Aug 14, 2015 (3 ys) in the Coloro mountins t Frisco (ner Breckenrige). The course is for users who hve GAMS bckgroun. Detils re foun t Further informtion n other courses re liste on Note I lso give custom courses for iniviul groups couple of times yer. 7 Unsubscribe or subscribe to future issues of this newsletter Plese unsubscribe through the web form vilble t: Those who wish to subscribe to future issues cn o this trough the newsletter section of This newsletter is not prouct of GAMS Corportion lthough it is istribute with their coopertion. July 7,