RE: MI-L mapbasic Update table with custom function
OK, what's the trick? Corner=strpcorner(stable2.location) doesn't work. I don't want to write code to loop through the table, if I don't have to. Looping through the table is going to be slow. The update statement (for some reason) doesn't recognize table field names in custom functions. I have written a MBX with a simple function and I can pass values to fill the field. When I tried to use an alias(ie - Function xx(str as alias)as string), its fatal for Mapinfo 6.5 (win2000 reports an illegal operation closes Mapinfo). Someone must have discovered this before. I have a hard time believing there isn't a way to update a field with a custom function without looping through the table or some other work around. (I can do it in access.) When I sketched out my flow diagram, it never occurred to me that this couldn't be done. Its back to the drawing board. The Manual says that you can use custom functions in Select statements. Has anyone had any luck? -Original Message- From: B. Thoen [mailto:[EMAIL PROTECTED] Sent: Monday, April 26, 2004 5:07 PM To: Jacques Paris Cc: Cummings, Mike; Mapinfo-L Subject: RE: MI-L mapbasic Update table with custom function No, that's not the case. In MapBasic, you can use custom functions in 'update' statements. In fact, this is a little known trick for rapidly updating tables rather than using the slower 'Do While...Loop' technique. You might need to add the table name to the variable (e.g. Corner=strpcorner(stable2.location)), but that's just a stab in the dark. Check your spelling too -- 'location' may actually be 'loaction' in the table, or something like that. - Bill Thoen On Mon, 26 Apr 2004, Jacques Paris wrote: My interpretation is that the expression used to update a column must be written with the MapBasic vocabulary. I deduce that from the fact that update as many other functions can be run from the MapBasic window that does not support any external calls, i.e. calls to custom functions that are not part of the MB set and must be supplied by the user, and the MB window does not allow that. Jacques Paris e-mail [EMAIL PROTECTED] MapBasic-MapInfo support http://www.paris-pc-gis.com -Original Message- From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: 26-Apr-04 18:14 To: Mapinfo-L Subject: MI-L mapbasic Update table with custom function I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11533 - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11544
RE: MI-L mapbasic Update table with custom function
Mike, I have used functions in the past for doing this kind of update, but i always called the column by its column number see the code below tis v fast and handy, but you have to watch some updates because they all occurr concurrently, so in the example below, i also update column3, but it gets updated with the OLD values from column 2, not the new ones being calculated by the function in teh first part of the update. include mapbasic.def declare sub main() declare function mysquare(byval mycolumnum as integer) as float sub main Open Table D:\tableone.TAB as mytest ' now i update column two by calling the function against column 1 Update mytest Set Field2 = mysquare(1), Field3 = str$(Field2/3) browse * from mytest end sub ' my function to return the square of the first column Function mysquare(byval mycolumnum as integer) as float mysquare = mytest.col(mycolumnum) * mytest.col(mycolumnum) end function hth r * This e-mail message, and any files transmitted with it, are confidential and intended solely for the use of the addressee. If this message was not addressed to you, you have received it in error and any copying, distribution or other use of any part of it is strictly prohibited. Any views or opinions presented are solely those of the sender and do not necessarily represent those of the British Geological Survey. The security of e-mail communication cannot be guaranteed and the BGS accepts no liability for claims arising as a result of the use of this medium to transmit messages from or to the BGS. .http://www.bgs.ac.uk * - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11545
RE: MI-L mapbasic Update table with custom function
It does work. So there must be some word that you have used that is confusing the compiler Update stable2 Set MTRS = Left$(BM,1)+TWN+RGE+Right$(0+SEC, 2), CORNER=strpcorner(LOCATION) A few thing to look into: - is stable2 a variable or the real name of the table ? - You haven't made a selection from your table and forgot to select all the columns ? - does strpcorner take the parameter ByVal ? HTH Peter Horsbøll Møller GIS Udvikler Geographical Information IT COWI A/S Odensevej 95 5260 Odense S. Telefon 6311 4900 Direkte 6311 4908 Mobil5156 1045 Telefax 6311 4949 E-mail [EMAIL PROTECTED] http://www.cowi.dk http://www.cowi.dk/ From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: Tue 27-Apr-04 18:17 To: B. Thoen; Jacques Paris Cc: Mapinfo-L Subject: RE: MI-L mapbasic Update table with custom function OK, what's the trick? Corner=strpcorner(stable2.location) doesn't work. I don't want to write code to loop through the table, if I don't have to. Looping through the table is going to be slow. The update statement (for some reason) doesn't recognize table field names in custom functions. I have written a MBX with a simple function and I can pass values to fill the field. When I tried to use an alias(ie - Function xx(str as alias)as string), its fatal for Mapinfo 6.5 (win2000 reports an illegal operation closes Mapinfo). Someone must have discovered this before. I have a hard time believing there isn't a way to update a field with a custom function without looping through the table or some other work around. (I can do it in access.) When I sketched out my flow diagram, it never occurred to me that this couldn't be done. Its back to the drawing board. The Manual says that you can use custom functions in Select statements. Has anyone had any luck? -Original Message- From: B. Thoen [mailto:[EMAIL PROTECTED] Sent: Monday, April 26, 2004 5:07 PM To: Jacques Paris Cc: Cummings, Mike; Mapinfo-L Subject: RE: MI-L mapbasic Update table with custom function No, that's not the case. In MapBasic, you can use custom functions in 'update' statements. In fact, this is a little known trick for rapidly updating tables rather than using the slower 'Do While...Loop' technique. You might need to add the table name to the variable (e.g. Corner=strpcorner(stable2.location)), but that's just a stab in the dark. Check your spelling too -- 'location' may actually be 'loaction' in the table, or something like that. - Bill Thoen On Mon, 26 Apr 2004, Jacques Paris wrote: My interpretation is that the expression used to update a column must be written with the MapBasic vocabulary. I deduce that from the fact that update as many other functions can be run from the MapBasic window that does not support any external calls, i.e. calls to custom functions that are not part of the MB set and must be supplied by the user, and the MB window does not allow that. Jacques Paris e-mail [EMAIL PROTECTED] MapBasic-MapInfo support http://www.paris-pc-gis.com -Original Message- From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: 26-Apr-04 18:14 To: Mapinfo-L Subject: MI-L mapbasic Update table with custom function I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11533 - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11544
Re: MI-L mapbasic Update table with custom function
Here's a complete example of creating a small table and updating a column with a custom function: '--- Declare Function FirstWord (ByVal sText As String) As String Close All Interactive Create Table TEST ( Corner Char (25), Location Char (25)) File ApplicationDirectory$() test.tab Insert Into TEST (Location) Values (One Fish) Insert Into TEST (Location) Values (Two Fish) Insert Into TEST (Location) Values (Red Fish) Insert Into TEST (Location) Values (Blue Fish) Update TEST Set Corner=FirstWord(Location) Commit Table TEST Browse * From TEST Function FirstWord (ByVal sText As String) As String Dim sWord As String sWord = Left$(sText, InStr(1, sText, )-1) FirstWord = sWord End Function '--- Cummings, Mike wrote: OK, what's the trick? Corner=strpcorner(stable2.location) doesn't work. I don't want to write code to loop through the table, if I don't have to. Looping through the table is going to be slow. The update statement (for some reason) doesn't recognize table field names in custom functions. I have written a MBX with a simple function and I can pass values to fill the field. When I tried to use an alias(ie - Function xx(str as alias)as string), its fatal for Mapinfo 6.5 (win2000 reports an illegal operation closes Mapinfo). Someone must have discovered this before. I have a hard time believing there isn't a way to update a field with a custom function without looping through the table or some other work around. (I can do it in access.) When I sketched out my flow diagram, it never occurred to me that this couldn't be done. Its back to the drawing board. The Manual says that you can use custom functions in Select statements. Has anyone had any luck? -Original Message- From: B. Thoen [mailto:[EMAIL PROTECTED] Sent: Monday, April 26, 2004 5:07 PM To: Jacques Paris Cc: Cummings, Mike; Mapinfo-L Subject: RE: MI-L mapbasic Update table with custom function No, that's not the case. In MapBasic, you can use custom functions in 'update' statements. In fact, this is a little known trick for rapidly updating tables rather than using the slower 'Do While...Loop' technique. You might need to add the table name to the variable (e.g. Corner=strpcorner(stable2.location)), but that's just a stab in the dark. Check your spelling too -- 'location' may actually be 'loaction' in the table, or something like that. - Bill Thoen On Mon, 26 Apr 2004, Jacques Paris wrote: My interpretation is that the expression used to update a column must be written with the MapBasic vocabulary. I deduce that from the fact that update as many other functions can be run from the MapBasic window that does not support any external calls, i.e. calls to custom functions that are not part of the MB set and must be supplied by the user, and the MB window does not allow that. Jacques Paris e-mail [EMAIL PROTECTED] MapBasic-MapInfo support http://www.paris-pc-gis.com -Original Message- From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: 26-Apr-04 18:14 To: Mapinfo-L Subject: MI-L mapbasic Update table with custom function I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11533 -- - Bill Thoen GISnet, 1401 Walnut St., Suite C, Boulder, CO 80302 tel: 303-786-9961, fax: 303-443-4856 http://www.gisnet.com/ - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11547
RE: MI-L mapbasic Update table with custom function
Hello Mike, I see that several people have made suggestions about this one. Here are my thoughts: 1) You can indeed use a custom function in an UPDATE statement, but not sub(s). This method can only be used in a MB program and not on the MB window command line. 2) Remember that you pass back a return value in MapBasic by assigning the function name itself to something as if it were a variable. It's very easy to forget this and have functions returning incorrect values. 3) The function can accept parameters from field names or MapBasic variable that are in scope. 4) I don't think it matters if the variables are passed byval or not. I am sure values passed not byval (=by reference), and modified by the function, are not stored back to the table. This is different from passing a variable by reference. 5) Your data types should be preferably identical but at least compatible (data type promotions like smallint-integer-float) are OK. 6) Remember that your column names should not conflict with variable names. If so, variable names will take precedence. E.g. If you have a variable called location with a type incompatible with strpcorner(), that could be your problem. 7) You can break statements along multiple lines so the Corner=strpcorner(location) which appears to be on a separate line in your message will be fine. The comma at the end of the preceding line makes it valid. Unlike some other languages you do not need to use statement continuation marks over multiple lines. Regards, Warren Vick Europa Technologies Ltd. http://www.europa-tech.com -Original Message- From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: 26 April 2004 23:14 To: Mapinfo-L Subject: MI-L mapbasic Update table with custom function I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11530 - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11550
RE: MI-L mapbasic Update table with custom function
Thanks for the sample code and all the help. ByVal is the key. I know tried using ByVal before my first e-mail; but the function returned a null value. After running your code, I see that I have a problem with the function also. (I had originally written this code in visual basic and converted it to Mapbasic.) The functions (between the two) are just a little different. It seems I screwed up the conversion. Again thanks to all! -Original Message- From: Bill Thoen [mailto:[EMAIL PROTECTED] Sent: Tuesday, April 27, 2004 10:10 AM To: Cummings, Mike Subject: Re: MI-L mapbasic Update table with custom function BTW, you must pass the argument by value, not reference. In your example below, you've declared Function xx (str as ...). It must be Function xx (ByVal str ... Cummings, Mike wrote: OK, what's the trick? Corner=strpcorner(stable2.location) doesn't work. I don't want to write code to loop through the table, if I don't have to. Looping through the table is going to be slow. The update statement (for some reason) doesn't recognize table field names in custom functions. I have written a MBX with a simple function and I can pass values to fill the field. When I tried to use an alias(ie - Function xx(str as alias)as string), its fatal for Mapinfo 6.5 (win2000 reports an illegal operation closes Mapinfo). Someone must have discovered this before. I have a hard time believing there isn't a way to update a field with a custom function without looping through the table or some other work around. (I can do it in access.) When I sketched out my flow diagram, it never occurred to me that this couldn't be done. Its back to the drawing board. The Manual says that you can use custom functions in Select statements. Has anyone had any luck? -Original Message- From: B. Thoen [mailto:[EMAIL PROTECTED] Sent: Monday, April 26, 2004 5:07 PM To: Jacques Paris Cc: Cummings, Mike; Mapinfo-L Subject: RE: MI-L mapbasic Update table with custom function No, that's not the case. In MapBasic, you can use custom functions in 'update' statements. In fact, this is a little known trick for rapidly updating tables rather than using the slower 'Do While...Loop' technique. You might need to add the table name to the variable (e.g. Corner=strpcorner(stable2.location)), but that's just a stab in the dark. Check your spelling too -- 'location' may actually be 'loaction' in the table, or something like that. - Bill Thoen On Mon, 26 Apr 2004, Jacques Paris wrote: My interpretation is that the expression used to update a column must be written with the MapBasic vocabulary. I deduce that from the fact that update as many other functions can be run from the MapBasic window that does not support any external calls, i.e. calls to custom functions that are not part of the MB set and must be supplied by the user, and the MB window does not allow that. Jacques Paris e-mail [EMAIL PROTECTED] MapBasic-MapInfo support http://www.paris-pc-gis.com -Original Message- From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: 26-Apr-04 18:14 To: Mapinfo-L Subject: MI-L mapbasic Update table with custom function I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11533 - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11544 -- - Bill Thoen GISnet, 1401 Walnut St., Suite C, Boulder, CO 80302 tel: 303-786-9961, fax: 303-443-4856 http://www.gisnet.com/ - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11551
MI-L mapbasic Update table with custom function
I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11530
RE: MI-L mapbasic Update table with custom function
My interpretation is that the expression used to update a column must be written with the MapBasic vocabulary. I deduce that from the fact that update as many other functions can be run from the MapBasic window that does not support any external calls, i.e. calls to custom functions that are not part of the MB set and must be supplied by the user, and the MB window does not allow that. Jacques Paris e-mail [EMAIL PROTECTED] MapBasic-MapInfo support http://www.paris-pc-gis.com -Original Message- From: Cummings, Mike [mailto:[EMAIL PROTECTED] Sent: 26-Apr-04 18:14 To: Mapinfo-L Subject: MI-L mapbasic Update table with custom function I tried to compile this code: Update stable2 Set MTRS = Left$(bm,1)+Twn+Rge+right$(0+sec,2), Corner=strpcorner(location) (Where MTRS, BM, TWN, RGE, SEC, corner Location are fields in stable2 and strpcorner is a custom function) and I get this error message: Subroute Argument location not defined. Why doesn't this work? Shouldn't Mapbasic recognize that location is a field name? - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11530 - List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 11532
