Richard Palmer-Jones wrote:
Why does:
gen str3 hhno = substr(string(hholdid),-3,3)
give me +09?
hholdid is double - format %12.0f
Well I know why - it reads the exponent. I did it by:
gen int hhno = hholdid - 1000 * int(hholdid/1000)
Also, I see one can use "tostring" which behaves correctly, and then extract
the last three characters using substr()
- but I would still like to know why.
--------------------------------------------------------------------------------
Use the format option for the -string()- function, i.e., -string(n,"%fmt")-
(the second syntax in the help file), when converting large-valued numeric
variables to string.
The first rule, though, is to start out using string, not numeric, variables
for ID numbers.
Joseph Coveney
. set obs 1
obs was 0, now 1
. generate double hholdid = 1234567890
. list
+-----------+
| hholdid |
|-----------|
1. | 1.235e+09 |
+-----------+
. format hholdid %12.0f
. list
+------------+
| hholdid |
|------------|
1. | 1234567890 |
+------------+
. gen str hhno = string(hholdid)
. list
+-----------------------+
| hholdid hhno |
|-----------------------|
1. | 1234567890 1.23e+09 |
+-----------------------+
. replace hhno = substr(string(hholdid),-3,3)
(1 real change made)
. list
+-------------------+
| hholdid hhno |
|-------------------|
1. | 1234567890 +09 |
+-------------------+
. replace hhno = string(hholdid, "%12.0f")
hhno was str8 now str10
(1 real change made)
. list
+-------------------------+
| hholdid hhno |
|-------------------------|
1. | 1234567890 1234567890 |
+-------------------------+
. replace hhno = substr(string(hholdid, "%12.0f"),-3,3)
(1 real change made)
. list
+-------------------+
| hholdid hhno |
|-------------------|
1. | 1234567890 890 |
+-------------------+
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