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series of fixes and improvements (#2563)
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@ -256,7 +256,7 @@ l / => 5 2 3 4
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/ Lists can also be used for indexing and indexed assignment
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l[1 3] / => 2 4
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l[1 3]: 1 3
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l / => 1 1 3 3
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l / => 5 1 3 3
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/ Lists can be untyped/mixed type
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l:(1;2;`hi)
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@ -290,6 +290,7 @@ last 1 2 3 / => 3
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/ Take (#), drop (_) and find (?) are also useful working with lists
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l:1 2 3 4 5 6 7 8 9
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l:1+til 9 / til is a useful shortcut for generating ranges
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/ take the first 5 elements
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5#l / => 1 2 3 4 5
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/ drop the first 5
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@ -297,7 +298,7 @@ l:1 2 3 4 5 6 7 8 9
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/ take the last 5
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-5#l / => 5 6 7 8 9
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/ drop the last 5
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-5_l / => 1 2 3 4 5
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-5_l / => 1 2 3 4
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/ find the first occurance of 4
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l?4 / => 3
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l[3] / => 4
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@ -397,7 +398,7 @@ k!t
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/ => id| c1 c2 c3
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/ => --| --------
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/ => 1 | 1 4 7
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/ => 2 | 2 5 8
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/ => 2 | 3 5 8
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/ => 3 | 3 6 9
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/ We can also use this shortcut for defining keyed tables
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@ -455,7 +456,7 @@ f[2] / => 4
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/ however using a dictionary as a single argument can overcome this
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/ allows for optional arguments or differing functionality
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d:`arg1`arg2`arg3!(1.0;2;"my function argument")
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{x[`arg1]+x[`arg2]}[d] / => 3.0
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{x[`arg1]+x[`arg2]}[d] / => 3f
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/ Functions in q see the global scope
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a:1
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@ -464,6 +465,7 @@ a:1
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/ However local scope obscures this
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a:1
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{a:2;:a}[] / => 2
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a / => 1
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/ Functions cannot see nested scopes (only local and global)
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{local:1;{:local}[]}[] / throws error as local is not defined in inner function
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@ -494,11 +496,11 @@ t:([]name:`Arthur`Thomas`Polly;age:35 32 52;height:180 175 160;sex:`m`m`f)
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/ equivalent of SELECT * FROM t
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select from t / (must be lower case, and the wildcard is not necessary)
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/ => name age height
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/ => -----------------
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/ => Arthur 35 180
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/ => Thomas 32 175
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/ => Polly 52 160
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/ => name age height sex
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/ => ---------------------
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/ => Arthur 35 180 m
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/ => Thomas 32 175 m
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/ => Polly 52 160 f
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/ Select specific columns
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select name,age from t
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@ -523,6 +525,7 @@ select name, feet:floor height*0.032, inches:12*(height*0.032) mod 1 from t
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/ => ------------------
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/ => Arthur 5 9.12
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/ => Thomas 5 7.2
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/ => Polly 5 1.44
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/ Including custom functions
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select name, growth:{[h;a]h%a}[height;age] from t
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@ -534,18 +537,18 @@ select name, growth:{[h;a]h%a}[height;age] from t
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/ The where clause can contain multiple statements separated by commas
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select from t where age>33,height>175
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/ => name age height
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/ => -----------------
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/ => Arthur 35 180
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/ => name age height sex
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/ => ---------------------
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/ => Arthur 35 180 m
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/ The where statements are executed sequentially (not the same as logical AND)
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select from t where age<40,height=min height
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/ => name age height
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/ => -----------------
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/ => Thomas 32 175
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/ => name age height sex
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/ => ---------------------
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/ => Thomas 32 175 m
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select from t where (age<40)&(height=min height)
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/ => name age height
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/ => ---------------
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/ => name age height sex
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/ => -------------------
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/ The by clause falls between select and from
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/ and is equivalent to SQL's GROUP BY
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@ -585,7 +588,7 @@ t
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/ => Polly 52 160 f
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/ Insert however is in place, it takes a table name, and new data
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`t insert (`John;25;178;`m)
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`t insert (`John;25;178;`m) / => ,3
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t
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/ => name age height sex
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/ => ---------------------
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