Hello, Other people are probably better qualified to weigh in on the best ways to manage packages in a Pharo image, but this is what I do: 1) Left click on the "desktop" to bring up the "world menu" and select "Monticello Browser." 2) Click the "+Repository" button and select "smalltalkhub.com" from the popup menu. 3) Type 'EvanDonahue' and 'Lazy' inside the provided quotes next to owner: and project:, respectively (user and password can be left ''). Then click OK. 4) Highlight "Lazy-Core-EvanDonahue.26.mcz" on the right panel (may be 26 or any other number) and click the "Browse" button to explore the classes and methods without actually installing in your image. 5) Click the "Load" button to install the classes in the image. You may also want to install Lazy-Tests just to have some code examples to look at. 6) To remove everything later, open Monticello again, search for "Lazy," right-click Lazy-Core in the left pane, and "unload" As for your use case, what you have written should work, but if you just want a ton of 1's, you can use LazyList repeat: 1 There are other class methods of increasing generality for generating infinite lists, but of course you can always use #collect: and friends to compose appropriately. LazyList is technically still "under development," but it should be feature complete for most uses. Let me know if there's any functionality it's missing, or if you're wondering whether and how it can do something. If you want to say any more about the operations you are trying to perform, I can be more specific about how to do them. Roughly, aside from the infinite methods, the API follows the standard Pharo collections. And also welcome to Pharo. It's a trip. Cheers, Evan -- View this message in context: http://forum.world.st/Is-lazy-evaluation-of-infinite-series-possible-tp48979... Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

The fibonacciSequence example was really helpful. I made a new class PowerSeries, a subclass of Generator. Then I defined a binary operation + as follows: + aPowerSeries ^ PowerSeries on: [ :ps | | a b | [ a := self next. b := aPowerSeries next. ps yield: (a + b) ] repeat ] This works perfectly. But now I am struggling with how to define multiplication. When I do PS1 * PS2, the first yield should be a := PS1 next. b := PS2 next. ps yield (a * b). Thereafter would come the PowerSeries, call it PSNew, (PS2 .* a) + (PS1 * PS2'), where .* is scalar multiplication (easy to implement) and PS2' is the original PS2 (i.e., rewound 1). I see several problems here. It looks like I need a way to clone (fork?) a PowerSeries since in this computation I need both the current PS2 and the original PS2 and be able to operate with them independently. Second, how do I define the generator so that it first yields the scalar (a*b) and thereafter is represented by the PowerSeries PSNew? Finally, will the recursion in the definition of * blow up rapidly? -- View this message in context: http://forum.world.st/Is-lazy-evaluation-of-infinite-series-possible-tp48979... Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Multiplication of power series looks tricky as for the term k of the resulting power series you need to access terms where sum index value to k. (ps1 next: i) and (ps2 next: k - i). Somehow the bloc of code defining the multiplicated serie needs to know about its current rank k. You should not need a dedicated .* operator, you can handle it with only * operator with appropriate object testing. No real answer Le 30/05/2016 21:47, Erisa a écrit :

The fibonacciSequence example was really helpful. I made a new class PowerSeries, a subclass of Generator. Then I defined a binary operation + as follows:

+ aPowerSeries ^ PowerSeries on: [ :ps | | a b | [ a := self next. b := aPowerSeries next. ps yield: (a + b) ] repeat ]

This works perfectly. But now I am struggling with how to define multiplication. When I do PS1 * PS2, the first yield should be a := PS1 next. b := PS2 next. ps yield (a * b). Thereafter would come the PowerSeries, call it PSNew, (PS2 .* a) + (PS1 * PS2'), where .* is scalar multiplication (easy to implement) and PS2' is the original PS2 (i.e., rewound 1). I see several problems here. It looks like I need a way to clone (fork?) a PowerSeries since in this computation I need both the current PS2 and the original PS2 and be able to operate with them independently. Second, how do I define the generator so that it first yields the scalar (a*b) and thereafter is represented by the PowerSeries PSNew? Finally, will the recursion in the definition of * blow up rapidly?

-- Dr. Geo http://drgeo.eu

Hi Erisa, one solution, using your notation, could eg be * aPowerSeries ^ PowerSeries on: [ :generator | |a b| a:=OrderedCollection new. b:=OrderedCollection new. [ a add: self next. b add: aPowerSeries next. generator yield: a asDhbVector * b asDhbVector reverse ] repeat ] the multiplication of DhbVectors is the same as your ".*". DhbVector is not in the standard pharo, it is part of the polymath project, i was just too lazy to program that part by hand, but changing that should be no problem. werner On 05/30/2016 09:47 PM, Erisa wrote:

The fibonacciSequence example was really helpful. I made a new class PowerSeries, a subclass of Generator. Then I defined a binary operation + as follows:

+ aPowerSeries ^ PowerSeries on: [ :ps | | a b | [ a := self next. b := aPowerSeries next. ps yield: (a + b) ] repeat ]

This works perfectly. But now I am struggling with how to define multiplication. When I do PS1 * PS2, the first yield should be a := PS1 next. b := PS2 next. ps yield (a * b). Thereafter would come the PowerSeries, call it PSNew, (PS2 .* a) + (PS1 * PS2'), where .* is scalar multiplication (easy to implement) and PS2' is the original PS2 (i.e., rewound 1). I see several problems here. It looks like I need a way to clone (fork?) a PowerSeries since in this computation I need both the current PS2 and the original PS2 and be able to operate with them independently. Second, how do I define the generator so that it first yields the scalar (a*b) and thereafter is represented by the PowerSeries PSNew? Finally, will the recursion in the definition of * blow up rapidly?

-- View this message in context: http://forum.world.st/Is-lazy-evaluation-of-infinite-series-possible-tp48979... Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.