In PyQ I can create a dictionary and transpose it with flip to get a table...
q.set(':alpha', q('!', ["Name", "Ask", "Bid", "Time"], ()).flip)
However, as expected, when I load it in q and retrieve the meta data it shows the char type for all of the columns as symbols...
>>> q.get(':alpha').show()
Name Ask Bid Time
---------------------------------------------------------------
"BTC" "16351.0" "16350.0" "2017-12-12T17:32:33.09"
"ETH" "589.89999993" "585.25" "2017-12-12T17:32:32.697"
"LTC" "297.0" "296.29570358" "2017-12-12T17:32:32.353"
"BTC" "16355.0" "16351.0" "2017-12-12T17:32:44.777"
"ETH" "589.89999993" "585.25" "2017-12-12T17:32:42.15"
"LTC" "297.99940398" "296.29570359" "2017-12-12T17:32:44.433"
"BTC" "16359.99999998" "16350.0" "2017-12-12T17:32:53.713"
"ETH" "589.89999993" "585.2500001" "2017-12-12T17:32:53.197"
"LTC" "297.99940398" "295.0" "2017-12-12T17:32:51.37"
"BTC" "16355.0" "16350.0" "2017-12-12T17:33:02.433"
"ETH" "585.2500001" "585.25" "2017-12-12T17:33:03.497"
"LTC" "297.99940397" "295.0" "2017-12-12T17:33:01.463"
>>> q()
q)\l alpha
`alpha
q)meta alpha
c | t f a
----| -----
Name| s
Ask | s
Bid | s
Time| s
q)
Which I believe is what's causing the 'type error to be thrown by the console when I perform the following queries...
q)select Name, max Ask, max Bid, Time from alpha
'type
q)select max Ask, max Bid, Time by Name from alpha
'type
q)select from alpha where Bid=(max;Bid) fby Name
'type
q)select from alpha where Name=`BTC
Name Ask Bid Time
-----------------
I know in q I can issue the following command to achieve this...
q)alpha:([]Name:`symbol$(); Ask:`float$(); Bid:`float$(); Time:`datetime$())
q)meta alpha
c | t f a
----| -----
Name| s
Ask | f
Bid | f
Time| z
q)
What is the correct syntax to define the char type for each column in PyQ?
I was passing a datetime char type to a timestamp column. In q I would define these as...
q)table:([]date:`datetime$(); name:`symbol$())
q)meta table
c | t f a
----| -----
date| z
name| s
q)table:([]date:`timestamp$(); name:`symbol$())
q)meta table
c | t f a
----| -----
date| p
name| s
I was able to work around this by parsing the datetime to a timestamp and casting to K.timestamp([])...
Code below...
from bittrex.bittrex import Bittrex, API_V2_0
from datetime import datetime
import time
from pyq import q, K
get_bittrex = Bittrex(None, None)
starttime = time.time()
q.load(':alpha')
while True:
market_result = get_bittrex.get_market_summaries()['result']
for res in market_result:
market_name = res['MarketName']
ask = float(res['Ask'])
bid = float(res['Bid'])
last = float(res['Last'])
volume = float(res['Volume'])
dt = res['TimeStamp']
if market_name in ['USDT-BTC', 'USDT-ETH', 'USDT-LTC', 'USDT-XRP', 'USDT-NEO', 'USDT-BCC', 'USDT-ZEC', 'USDT-XMR', 'USDT-DASH']:
ts = datetime.strptime(dt, '%Y-%m-%dT%H:%M:%S.%f')
data = [market_name[5:], ask, bid, last, volume, ts]
q.upsert(':alpha', [data])
q.get(':alpha').show()
time.sleep(60.0)
Now returns the correct char type in my table...
q)meta alpha
c | t f a
----| -----
Name| s
Ask | f
Bid | f
Last| f
Vol | f
Time| p