It seems that TradeKing is closing to be another broker(Ally?), based on their website TradeKing.com How about their privious API connection by R (https://www.r-project.org/). Possibly, the new broker MAY NOT BE CONNECTED by R API. Is it true? Appreciated if someone tells me what I am misunderstood. -Jay PS) Is there any other brokers, which uses R for API connection?
It is just a personal reason. Recently many have favourite language, such as R or Python. I became R user by chance.
If I am correct, TradeKing was ONLY ONE broker which support R. So possibly there is NO (more) broker which use R, in US. However there are many which supports Python, which I am learning recently. Here is IB connection via Python.
R is a language for working with statistics. You are almost certainly referring to some library for R that interfaces to TradeKing's protocols. I have never used R, but I have adapted some trivial software in another language that did queries with TradeKing's protocols. The last time I looked into it, TradeKing used a protocol based on OpenAuth, XML, etc., very similar to what I believe is offered by TD Ameritrade, E-Trade and Tradier, the latter of which I was told got much of its initial technical staff from TradeKing.
Possibly you mean we can use R to connect servers of "TD Ameritrade, E-Trade and Tradier". If there is some known tool in R 1) to login 2) to get what I hold currently 3) to send my new order (matrix) to their server then, please let me know. More brokers supports Python than R, for API connection. Only a few allow R.